106
LAMPIRAN
107
Lampiran 1. Dua Puluh Produsen Cabai Segara Dunia No
Negara
Produksi (Juta Ton)
1
China
14,52
2
Mexico
1,94
3
Turkey
1,84
4
Indonesia
1,10
5
Spain
1,01
6
United States of America
0,93
7
Egypt
0,80
8
Nigeria
0,45
9
Republic of Korea
0,42
10
Netherlands
0,37
11
Algeria
0,32
12
Tunisia
0,30
13
Romania
0,25
14
Morocco
0,24
15
Italy
0,23
16
Ethiopia
0,22
17
Israel
0,20
18
Ghana
0,18
19
Serbia
0,17
20
Hungary
0,17
Sumber : FAOSTAT, 2011
108
Lampiran 2. Dua Puluh Produsen Cabai Kering Dunia No
Negara
Produksi (Juta Ton)
1
India
1.30
2
China
0.26
3
Pakistan
0.19
4
Thailand
0.17
5
Peru
0.14
6
Ethiopia
0.12
7
Myanmar
0.12
8
Viet Nam
0.11
9
Bangladesh
0.11
10
Ghana
0.09
11
Mexico
0.05
12
Nigeria
0.05
13
Egypt
0.05
14
Romania
0.04
15
Democratic Republic of the Congo
0.03
16
Benin
0.03
17
Bosnia and Herzegovina
0.02
18
Côte d'Ivoire
0.02
19
Hungary
0.02
20
Morocco
0.02
Sumber : FAOSTAT, 2011
SOP Cabai Merah Menggunakan Teknologi WiSH
Hari
Uraian
Keterangan
• Pilih lahan bekas jagung atau padi dan tidak H-30
H-21
banyak naungan BUKAN bekas tomat, terong atau cabai • Bajak 2x dan di rotary
• Persiapan persemaian
Persemaian dilakukan dalam kelambu yang kedap serangga kecil. Benih direndam dalam Actigrow atau BenPrima (10 cc atau 10 g/liter air) selama 30 menit. Bekas rendaman dapat disiramkan ke media semai.
• Pembuatan bedengan, L = 110-120cm, P = 15-
H-7
H-3 H-1 H-0
20m, T = 30-50cm, jarak antar bedengan = 6070cm, jarak antar tanaman = 60-70cm • Pembuatan lubang tanam dan pemasangan ajir dengan jarak 60x70 cm, serta pembuatan lubang pupuk dengan jarak 20 cm • Pemberian kompos dengan cara MENYEBARKAN dan DIADUK MERATA sebanyak 7 ton/Ha • Pemberian pupuk dasar a. NPK (16:16:16) 100 kg/Ha b. ZA 150 kg/ha c. KCl 100 kg/ha atau arang sekam 200 kg/ha • SANITASI GULMA SAMPAI BERSIH DI LAHAN MILIK Tanah diairi setinggi batas mulsa Tanam pagi hari sebelum pukul 10 atau sore hari
• Semprot FITPLANTA 5cc/liter air • Kocoran H+15 a) 10 kg NPK (16:16:16) Dicampur 150 b) 5 kg ZA liter air c) 5 kg KCl • Semprot FITPLANTA 5ml + 1 cc sabun cair /liter
• Vol. larutan semprot 100 lt/ha • Vol. kocor 100 ml/tnmn
air
• Kocoran H+30
a) b) c) d)
10 kg NPK (16:16:16) Dicampur 300 5 kg ZA liter air 5 kg KCl 700 ml ACTIGROW • Semprot FITPLANTA 5ml + 1 cc sabun cair /liter H+45 air
• Vol. larutan semprot 200 lt/ha • Vol. kocor 200 ml/tnmn
• Vol. larutan semprot 400 lt/ha • Vol. kocor 200 ml/tnmn
• Kocoran a) 10 kg NPK 16-16-16 Dicampur 300 b) 5 kg ZA liter air c) 5 kg KCl • Kocor 1,4 liter ACTIGROW dengan 140 liter air H+60 • Semprot FITPLANTA 5ml/liter air H+60, 74, 88, 102 H+60 dst
Semprot BIOGARD 5ml/liter air + sabun cair 1 cc/liter
• Vol. larutan semprot 400 lt/ha • Vol. kocor 200 ml/tnmn Vol. larutan semprot 400 lt/ha
Sanitasi dan pemusnahan buah cabai terserang antraknosa secara berkala (maksimal 2 hari sekali)
CATATAN - Persemaian dibuat dalam kelambu yang tidak memungkinkan serangga kecil (kutu kebul dan kutu daun masuk). Sebelum disemai benih direndam dalam Acti grow atau BenPrima (10 cc/liter) selama 30 menit, kemudian air bekas rendaman dsiramkan pada media semai - Pada kondisi lahan yang mendatar, jika tetangga lahan sudah menanam cabai atau tomat, perbatasan lahan ditanami tanaman jagung 3 lapis secara zig zag 1 bulan sebelum penanaman cabai atau dipagari dengan plastik dengan ketinggian minimal 1.0 m. - Jika menggunakan arang sekam sebagai pengganti pupuk KCl dalam pupuk kocoran, arang sekam harus direndam minimal selama 1 hari 1 malam, sebelum airnya digunakan untuk pengocoran.
PENGENALAN BEBERAPA GANGGUAN PENTING DALAM PRODUKSI CABAI DAN KEMUNGKINAN PENGENDALIANNYA
Widodo, Suryo Wiyono, dan Hermanu Triwidodo Departemen Proteksi Tanaman Fakultas Pertanian – Institut Pertanian Bogor
PENDAHULUAN
Tanaman cabai, sebagaimana tanaman lain dalam proses produksinya banyak mengalami gangguan, diantaranya hama dan penyakit. Untuk mencapai hasil pengendalian yang optimal diperlukan strategi yang baik yang berkaitan pemahaman terhadap komponenkomponen penyusun terjadinya gangguan tersebut. Pemahaman ini sangat penting dalam menyusun strategi pengendalian berdasarkan konsep pengendalian hama terpadu yang diharapkan memberikan hasil optimal dan ramah terhadap lingkungan ekosistem sehingga produksi cabai dapat berkelanjutan. Langkah awal dalam pengendalian terhadap gangguan pada tanaman adalah pengenalan penyebabnya, karena pengenalan tersebut dapat memahami lebih baik terhadap sifat-sifatnya. Buku panduan ini disusun dengan harapan setiap pembacanya yang berasal dari berbagai kalangan dapat memahami dengan mudah, terutama dalam mengindentifikasi penyebab gangguan tersebut dengan mudah. Dalam buku ini juga diberikan secara sederhana tentang berbagai faktor yang mempengaruhi perkembangan gangguan tersebut, sehingga pemakai dapat menentukan cara pengendalian yang lebih strategis.
Dalam identifikasi
penyebab gangguan tersebut, lebih ditekankan pada pengenalan gejala di lapang dengan cara yang sangat sederhana. Untuk identifikasi penyebab-penyebab tertentu tidak dapat dilakukan secara tepat dengan menggunakan buku ini.
DIAGRAM 1. ALUR DIAGNOSIS DI LAPANG BEBERAPA GANGGUAN PENTING PADA TANAMAN CABAI DI PESEMAIAN
A. Kecambah yang muncul hanya sedikit
Keadaan tanah pesemaian normal
Tanah pesemaian basah
Benih tidak berkecambah, membusuk, gagal muncul
Tanah terendam lebih dari 1 hari Cuaca dingin atau cahaya kurang
Kecambah muncul dan cepat membusuk ; cuaca lembab
- Benih terlalu lama - Ditamam terlalu dalam/dangkal - Tanah memadat/retak-retak - Terkena pupuk anorganik - Benih dimakanburung/ serangga tanah
Benih kekurangan oksigen Benih tampak normal
Masalah cuaca atau naungan
Benih busuk
patogen tular tanah
Kecambah muncul tidak merata
serangan belatung lalat bibit
terlihat cendawan seperti kapas terutama di pagi hari
Rebah kecambah oleh cendawan Pythium atau Sclerotium
busuk kering berwarna kecoklatan
Rebah kecambah oleh cendawan Rhizoctonia atau Fusarium (Gambar 1A, B)
tidak terlihat penampakan apapun
Kerusakan karena pupuk (anorganik) atau kandungan garam tanah tinggi
LANJUTAN DIAGRAM 1………… B. Kecambah banyak muncul; pertumbuhan terhambat
seragam terjadi di seluruh bedeng
kecambah terpilin atau bengkok; daun belang warna hijau muda; daun memutih; pangkal kecambah membengkak
- kerusakan karena pestisida (herbisida) - penempatan pupuk (anorganik)/pestsida pada kedalaman yang tidak sesuai - penanaman benih dengan kedalaman yang tidak sesuai
daun berbintik, terlihat berbercak; pinggiran daun seperti terbakar
- polusi udara - keracunan bahan kimia
pinggiran dan ujung daun seperti terbakar ; perakaran kecoklatan dan sedikit membusuk
pupuk anorganik yang terlalu banyak atau kandungan garam tanah yang terlalu tinggi
tanaman kerdil; terdapat belatung pada perakaran
kerusakan karena serangga (lalat bibit)
kecambah terpotong di permukaan tanah
serangan ulat tanah
perakaran berbintil
nematoda bintil akar
gejala berkelompok
perakaran busuk
cendawan tanah atau kandungan garam tanah tinggi
batang mengecil pada bagian dekat tanah terlihat cendawan seperti kapas
cendawan Pythium
busuk kering berwarna kecoklatan
Fusarium atau Rhizoctonia
tidak terlihat penampakan apapun
residu pestisida, pupuk, kandungan garam tinggi
DIAGRAM 2. ALUR DIAGNOSIS LAPANG GANGGUAN PENTING PADA TANAMAN CABAI SETELAH PINDAH TANAM
A. Tanaman bergejala berkelompok
pangkal batang membusuk
warna coklat tua atau hitam ; benangbenang cendawan tidak tampak jelas
busuk batang , cendawan Phytophthora capsici (Gambar 2A, B )
warna coklat ; batang di atas dan di bawah garis tanah rusak ; terlihat benang-benang cendawan berwarna putih dan butiran-butiran berwarna putih sampai coklat di sekitar pangkal batang
busuk pangkal batang, cendawan Sclerotium rolfsii (Gambar 3A,B)
pembusukan menggelangi di dekat permukaan tanah ; warna coklat
cabang atau ranting mati
di daerah berhawa sejuk
cendawan Pythium
di daerah berhawa panas
cendawan Rhizoctonia / Fusarium
warna coklat tua – hitam; agak kebasahan; terlihat lapisan tipis berwarna putih terutama pada pagi hari bercak warna putih di bagian tengah dan dikelilingi warna yang lebih gelap ; terlihat bintik-bintik hitam atau merah jambu gejala dimulai dari pucuk atau bunga; warna coklat sampai hitam ; koloni cendawan berwarna hitam terlihat dengan jelas
cendawan Phytophthora capsici
cendawan Stemphylium solani atau Colletotrichum capsici atau C. gloeosporioides (Gambar 4 A,B ) penyakit sentik disebabkan cendawan Choanephora cucurbitarum (Gambar 5 A, B )
LANJUTAN DIAGRAM 2 ……………. Tanaman bergejala berkelompok
tanaman layu atau warna tajuk berubah
kondisi akar baik terutama pada awal gejala ; jika batang dibelah berwarna coklat
kondisi perakaran jelek ; jika batang dibelah tidak terlihat warna coklat
kelayuan mendadak ; jika pangkal batang dipotong dan dicelupkan ke dalam air bening keluar lendir
Layu bakteri Pseudomonas solanacearum (Gambar 6 A, B)
kelayuan pelan-pelan didahului penguningan daun bawah ; jika pangkal batang dipotong dan dicelupkan ke air bening tidak keluar lendir
Layu Fusarium cendawan Fusarium oxysporum atau F. solani (Gambar 7 A, B )
tempat ditemukan tanaman sakit tanahnya tergenang / sangat becek lebih dari 1 hari
akar kekurangan oksigen karena tanah terlalu banyak air
akar terpotong atau membusuk
terlihat bintil-bintil pada akar
drainase tanah baik
nematoda perusak akar; kerusakan karena pupuk; kadar garam tanah tinggi
drainase tanah jelek
cendawan dalam tanah; kadar garam tanah tinggi
nematoda puru akar Meloidogyne (Gambar 8 A,B )
TABEL 1. JENIS GANGGUAN, FAKTOR-FAKTOR YANG MEMPERPARAH SERANGAN, DAN KEMUNGKINAN CARA PENGENDALIANNYA No. Jenis gangguan Benih busuk, tidak banyak 1. yang muncul
Faktor-faktor yang memperparah - tanah pesemaian terlalu padat - penggunaan pupuk anorganik atau pestisida ke tanah yang terlalu banyak - tanah terlalu becek/tergenang atau terlalu kering - kedalaman penanaman benih yang tidak tepat
Kemungkinan cara pengendalian - pengolahan tanah yang cukup dan penambahan bahan organik yang matang agar tanah gembur - drainase tanah pesemaian diperhatikan agar tidak terjadi penggenangan atau terlalu becek - bedengan pesemaian dibuat agak tinggi
2.
Rebah kecambah
- tanah pesemaian terlalu becek - benih tidak sehat dan disimpan terlalu lama pada suhu kamar - naungan pesemaian terlalu rapat sehingga aliran udara kurang baik - penggunaan pupuk organik yang belum matang
- memilih lokasi pesemaian yang baik drainasenya - menggunakan benih yang terjamin kualitasnya, jika membenihkan sendiri dipilih dari tanaman yang tumbuhnya terbaik dan dari buah yang tidak bergejala penyakit - membuat bedengan yang lebih tinggi dari tanah - menyimpan benih pada suhu dingin (di kulkas) - pupuk organik yang digunakan sudah matang - menjaga bedengan pesemaian jangan terlalu lembab - bedengan pesemaian ditutup dengan plastik bening selama 2 – 3 minggu dan dibiarkan terkena sinar matahari sebelum benih ditebar (solarisasi tanah) - jika diperlukan benih dapat diberi perlakuan fungisida berbahan aktif mancozeb, benomyl atau metalaxyl
3.
Busuk batang / buah Phytophthora
- drainase lahan kurang bagus - banyak terjadi pada musim hujan atau dilakukan penyiraman dari atas - pemupukan nitrat (urea) terlalu banyak - penanaman cabe terus menerus, atau dirotasi dengan terong, timun-timunan atau tomat
- menghindari tanah tergenang atau terlalu becek - menanam pada bedengan yang lebih tinggi - tidak terlalu banyak menggunakan pupuk nitrat jika kondisi tanah tidak terlalu masam dapat digunakan pupuk ammonium sulfat (ZA)
TABEL 1. (lanjutan) No.
Jenis gangguan
Faktor-faktor yang memperparah
Kemungkinan cara pengendalian - bedengan ditutup dengan jerami atau mulsa plastik untuk menghidari cipratan tanah oleh air hujan atau penyiraman - penggunaan pupuk kandang yang sudah matang - rotasi dengan tanaman famili graminae (jagung sorghum, rumput gajah dll) dapat membantu mengurangi penyakit
4.
Busuk pangkal batang Sclerotium
- banyak terjadi di daerah berudara hangat dan lembab - kandungan air tanah yang terlalu tinggi - sisa-sisa tanaman yang banyak tertinggal menjadi sumber makanan untuk bertahan
- pengolahan tanah yang dalam sehingga sklerotia cendawan dan sisa tanaman terkubur untuk mengurangi serangan, karena hanya sklerotia yang terletak di permukaan yang dapat menyerang - penutupan bedengan dengan jerami untuk mencegah kontaknya sklerotia dengan batang - jika memungkinkan, sebelum penanaman bedengan dapat ditutup dengan plastik bening (ketebalan 0.5 mm) selama 3 minggu dan dibiarkan terkena sinar matahari (solarisasi tanah)
5.
Layu Fusarium
- penyakit banyak terjadi pada tanah yang kandungan airnya tinggi (drainase jelek) dan suhu udara panas
- perbaikan drainase tanah - penggunaan pupuk kandang yang matang untuk memperkaya mikroba antagonis tanah - penambahan sisa-sisa kulit udang, kulit kerang yang dicampur dengan pupuk kandang ke dalam lubang tanam dan dibiarkan selama 1-2 minggu - jika memungkinan dapat dilakukan solarisasi tanah
TABEL 1 (lanjutan) No. Jenis gangguan Layu bakteri Pseudomonas 5. Solanacearum
Faktor-faktor yang memperparah - banyak terjadi di daerah dengan curah hujan tinggi atau pada musim hujan - serangan berat jika pemupukan N (nitrat), mis. urea terlalu tinggi - drainase tanah jelek - penanaman cabai terus menerus atau rotasi dengan famili solanaceae (terong, kentang, tomat, dll.)
Kemungkinan cara pengendalian - menghindari pemupukan nitrat yang terlalu tinggi; penggunaan mulsa plastik perak mempertinggi kemampuan serap nitrogen oleh tanaman menjadi lebih tinggi, oleh karena itu jika menggunakan mulsa ini, dosis nitrogen perlu dikurangi (kurang lebih 30 persen dari anjuran untuk setiap lokasi) - penggunaan pupuk ammonium sulfat (ZA) dilaporkan dapat mengurangi penyakit ini - rotasi tanaman dengan famili graminae (jagung, sorgum, dll.) - jika memungkinkan, solarisasi tanah dapat dipertimbangkan sebagai alternatif pengendalian
6.
Busuk buah Erwinia
- penyakit ini lebih banyak terjadi pada pasca panen, walaupun dapat juga menyerang di lapang terutama kondisi lembab dan hangat atau curah hujan tinggi - kerusakan oleh serangga di lapang mempercepat infeksi - pencucian buah setelah panen akan memperbesar terjadinya serangan dalam pengangkutan
- menghindari kerusakan buah oleh serangga di lapang - memperkecil pelukaan pada saat pemanenan - jika perlu dicuci, sebaiknya air ditambah dengan klorin (pemutih) dengan konsentrasi 0.5 % kemudian dikering anginkan
7.
Nematoda
- banyak terjadi di daerah dengan suhu hangat dengan kondisi tanah yang gembur (berpasir tinggi) - penanaman cabai terus menerus atau rotasi dengan tanaman solanaceae lainnya (tomat, terung)
- rotasi dengan tanaman rumput-rumputan (jagung, sorgum, atau padi gogo) - jika tanah dapat disawahkan, rotasi dengan padi sawah - jika diperlukan penggunaan nematisida dapat dilakukan, dengan catatan digilir jenis bahan aktifnya
TABEL 1. (Lanjutan ) No. Jenis gangguan Penyakit oleh virus 8.
9.
Antraknosa
Faktor-faktor yang memperparah - umumnya banyak terjadi pada musim kemarau, karena terkait dengan populasi vektornya - menanam tanaman inangnya secara terus menerus - menanam di dekat lahan yang terserang berat - menanam benih yang telah terinfeksi, beberapa virus dapat terbawa benih (misal tobacco mosaic virus /TMV)
Kemungkinan cara pengendalian Pengendalian virus lebih banyak diarahkan kepada penggunaan varietas tahan (sedang dikembangkan) dan pencegahan terjadinya kontak dengan vektor - menanam tanaman penahan (barier) seperti jagung sebelum penanaman dapat mengurangi peluang terserang oleh penyakit ini - eradikasi terhadap tanaman bergejala akan mengurangi sumber infeksi - untuk virus yang dapat terbawa benih, benih dapat direndam dengan larutan 10 % trisodium fosfat selama 2 jam - untuk virus yang dapat ditularkan secara mekanis (sepertii TMV), sebaiknya pemangkasan tunas tidak dilakukan pada tanaman yang sakit dahulu, atau setelah memangkas tanaman sakit tangan dicuci dahulu dengan dterjen atau alkohol 70 %
- banyak terjadi pada musim hujan, atau kondisi lahan yang terlalu lembab - dapat bertahan pada sisa tanaman yang jatuh di tanah dan akan menjadi sumber infeksi, oleh karena itu penanaman terus menerus akan meberi peluang semakin besar untuk terserang bagi tanaman berikutnya - penggunaan benih yang tidak sehat (penyebabnya dapat terbawa benih)
- menghindari lahan yang terlalu lembab - buah sakit yang jatuh sebaiknya tidak dibiarkan berada di lapang - tidak menanam terus menerus di satu lahan (perlu rotasi) - menggunakan benih yang terjamin kesehatannya, jika membenihkan sendiri pilih buah yang sehat (misal mengambil benih dari tanaman pada musim kemarau akan memperkecil peluang benih membawa penyebab penyakit) - jika diperlukan dapat digunakan fungisida yang dianjurkan, dengan menggilir jenis bahan aktifnya
TABEL 1 (Lanjutan…..) No. Jenis gangguan 10. Tungau, Thrips, Kutu Daun, Kutu Kebul
Faktor-faktor yang memperparah Kemungkinan cara pengendalian - Banyak terjadi pada musim kemarau /curah hujan, - Jika tidak banyak hujan, tungau dan thrips dapat tanaman terlindung dikendalikan dengan penyemprotan tajuk tanaman - Menanam di sekitar lahan yang terserang berat oleh dengan air dari arah bawah hama-hama tersebut - Untuk kutu kebul, penyemprotan dengan sabun - Khusus untuk kutu daun, ledakan sering terjadi karena mandi (bukan deterjen) aplikasi insektisida yang intensif untuk mengendalikan - Tumpang sari dengan bawang-bawangan dapat hama lainnya yang dapat membunuh predator kutu daun membantu mencegah kutu daun dan tungau - Penanaman bunga Tagetes (jawer kotok) di sekitar pertanaman membantu mencegah serangan Thrips dan kutu kebul - Penyemprotan dengan cairan bawang putih diketahui dapat mengendalikan tungau dan kutu daun - Pemasangan papan/plastik berwarna kuning dan diolesi perekat untuk menjebak kutu daun dan kutu kebul, sedangkan yang berwarna biru muda untuk menjebak thrips - Jika diperlukan penggunaan pestisida, digunakan secara tepat dan pastikan bahan aktifnya tidak membunuh predator kutu daun
Gejala beberapa gangguan pada tanaman cabe
Gambar 1 A. Gejala rebah kecambah
Gambar 1B. Gejala rebah kecambah
Gambar 2 A. Busuk batang Phytophthora
Gambar 2B. Gejala pada pangkal batang
Gambar 3A. Busuk pangkal batang Sclerotium
Gambar 3B. Cendawan Sclerotium Pada pangkal batang
Gambar 4A. Gejala mati ranting oleh Colletotrichum
Gambar 4B. Gejala bercak Stemphylium pada cabang
Gambar 5A. Gejala penyakit sentik pada cabang /ranting
Gambar 5B. Cendawan penyebab sentik Choanephora cucurbitarum
Gambar 6A. Gejala layu bakteri Pseudomonas solanacearum
Gambar 6B. Lendir bakteri yang keluar air bening
Gambar 7A. Gejala layu Fusarium di lapang (terlihat penguningan tajuk)
Gambar 7B. Warna coklat pada pembuluh akibat serangan Fusarium
Gambar 8A. Gejala serangan nematoda (tanaman merana seperti kekurangan hara)
Gambar 8B. Sistem perakaran yang terserang nematoda (akar berbintil-bintil kecil)
Gambar 9.
Gambar 10. Gejala virus
Gejala virus
Gambar 11. Gejala virus
Gambar 12. Gejala oleh TMV
Gambar 13. Busuk buah oleh Phytophthora capsici
Gambar 14. Busuk lunak pada buah oleh bakteri Erwinia
Gambar 15. Busuk buah oleh cendawan Botrytis cinerea (daun sakit yang menempel adalah sumber infeksi)
Gambar 16. Busuk ujung buah karena kekurangan kalsium (Ca)
Gambar 17A. Kerusakan oleh kutu daun
Gambar 17B. Penampakan tanaman Terserang kutu daun
Gambar 18. Gejala serangan tungau pada daun (daun melengkung ke bawah)
Gambar 19. Gejala serangan Thrips pada daun (daun melengkung ke atas
Gambar 20. Bercak daun Cercospora
Gambar 21. Bercak daun Stemphylium
Gambar 22. Gejala awal embun tepung
Gambar 23. Gejala lanjut embun tepung
Gambar 24. Antraknosa
Gambar 25. Serangan tungau pada buah
Gambar 26. Serangan Thrips pada buah
Guide Guide Guide International Cooperators’
AVRDC
World Vegetable Center
February 2005 AVRDC pub # 05-620
Suggested Cultural Practices for Chili Pepper by T. Berke1, L.L. Black, N.S. Talekar, J.F. Wang, P. Gniffke, S.K. Green, T.C. Wang, and R. Morris
Introduction Chili pepper (Capsicum annuum) is a popular vegetable valued around the world for the color, flavor, spice, and nutritional value it contributes to many meals (Fig. 1). Pepper varieties display a wide range of plant and fruit traits, and production practices vary greatly from region to region. The following recommendations were developed at AVRDC in the Taiwan lowlands. Modifications may be needed to take into account different soils, weather, pests and diseases.
Climate and soil requirements Chili pepper is better adapted to hot weather than is sweet pepper, but it does not set fruit well when night temperatures are greater than 24°C. Optimum day temperatures for chili pepper growth range from 20 to 30°C. When the temperature falls below 15°C or exceeds 32°C for extended periods, growth and yield are usually reduced. Peppers are photoperiod-insensitive (daylength does not affect flowering or fruit set).
Fig. 1. Chili pepper
especially consumer preferences for the shape, color and degree of pungency of fruits. Also consider local pest and disease pressures, genetic resistance to these local diseases, heat and drought tolerance, vine vigor, and seed costs.
Chili pepper grows best in a loam or silt loam soil with good water-holding capacity, but can grow on many soil types, as long as the soil is well drained. Soil pH should be between 5.5 and 6.8.
Growing peppers in a different season or under a different rotation system might provide higher yields and/or higher prices. Relay or intercropping might provide extra income from the same piece of land, and reduce insect and disease problems. Growers should calculate potential returns, and choose the cultivar and cropping system that serves them best.
Choosing a cultivar Chili pepper yields vary widely depending on cultivar and season. It's important to consider fruit quality,
Plant Breeder, Plant Pathologist, Entomologist, Plant Pathologist, Plant Breeder, Plant Pathologist, Plant Pathologist, and Soil Scientist at AVRDC. Edited by T. Kalb. For more information, contact Dr. Gniffke at
. AVRDC—The World Vegetable Center; P.O. Box 42, Shanhua; Taiwan 74199; ROC tel: (886-6) 583-7801 fax: (886-6) 583-0009 email: [email protected] www: avrdc.org 1
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Treating seed
at a density of 30,000 plants/ha, assuming 90% germination and 90% of seedlings are of good quality.
The primary seed-borne fungal pathogens are surface saprophytes such as Fusarium spp., Pythium spp., Rhizoctonia solani, and Colletotrichum spp. To minimize seed transmission, soak seeds in warm water (50°C) for 30 minutes, rinse them in cold water, and dry them before sowing. Apply a fungicide seed coating, such as 1 g of Benomyl 20% active ingredient (a.i.) wettable powder (WP) and 1 g Thiram 20% a.i. WP (or 0.8 g of Benlate [a mixture of Benomyl and Thiram] 50% a.i. WP) in 400 ml of water, so that the final concentration is 0.1% a.i.. Coat the seeds thoroughly by mixing 1 g of seeds with 1 ml of the fungicide suspension. Seeds may be dried at 20°C and 40% relative humidity or sown immediately.
Fill the seedling tray with sowing medium, such as peat moss, commercial potting soil, or a potting mix prepared from soil, compost, rice hulls, vermiculite, peat moss, and/or sand. The potting mix should have good water-holding capacity and good drainage. We recommend a mixture of 67% peat moss and 33% coarse vermiculite. If you use non-sterile components, we recommend that you sterilize your potting mixture by autoclaving or baking at 150°C for 2 hours. If seedlings are started in a raised soil bed, the soil should be sanitized by burning a 5-cm thick layer of rice straw or other dry organic matter on the bed. This also adds small amounts of P and K to the soil for the seedlings. Sow one seed per cell (or broadcast the seeds lightly in a seedbed) and cover 1 cm deep. Cover the seedlings with an insect-proof net (Fig. 2), or sow them inside a greenhouse or screenhouse. This provides shade and protects seedlings from heavy rain and pests, such as aphids, which transmit viruses. Upon emergence, water the seedlings thoroughly every morning or as needed (not too wet, not too dry), using a fine sprinkler. Irrigate with a 0.25% (w/v) solution of water-soluble or liquid fertilizer (10-1010) when two true leaves appear. If damping-off occurs, irrigate with a 0.25% Fig. 2. Seedlings growing under mesh net (w/v) solution of Benlate or similar fungicide.
The primary seed-borne viral pathogens are tobamoviruses, including tobacco mosaic virus (TMV), tomato mosaic virus (ToMV), and pepper mild mottle virus (PMMV). To minimize seed transmission, soak 2 g of seeds in 10 ml of 10% (w/v) trisodium phosphate (TSP) (Na3PO4 • 12 H2O) for 30 min, transfer them to a fresh 10% TSP solution for 2 hours, then rinse in running water for 45 minutes. This treatment can be done on freshly harvested or dry seeds. Or soak seeds for 4–6 hours in 5% (v/v) hydrochloric acid, then rinse in running water for 1 hour. Dry them for storage, or sow immediately. The primary seed-borne bacterial pathogen is Xanthomonas campestris pv. vesicatoria (Xcv). To minimize Xcv infection, soak 2 g of seeds in 10 ml of 1.3% (v/v) acetic acid (shake occasionally) for 4 hours, rinse the seeds with water three times, soak the seeds in 1.25% (v/v) Clorox for 5 minutes, and rinse under running water for 15 minutes. Or soak seeds in warm water (50°C) for 30 minutes, then dry or sow immediately. Pathogen-free seeds sown in sterile soil require no treatment.
If the seedlings have been grown in shade, harden them by gradually exposing them to direct sunlight over 4–5 days prior to transplanting. On the first day, expose them to 3–4 hours of direct sunlight. Increase the duration until they receive full sun on the fourth day.
Raising transplants Germination varies depending on variety, seed quality, and soil mixture. For optimum germination, sow seeds in a well-drained, sterile soilless mix at 25– 28°C, and water daily. Under these conditions, seeds will germinate in about eight days. Seeds will germinate in 13 days at 20°C and 25 days at 15°C; they may not germinate at all if temperatures are below 15 or above 35°C.
Field preparation The soil where chili peppers are to be grown should be carefully selected and prepared for the crop. Crop rotations should avoid sequences in which peppers are planted immediately following another Solana-
One gram contains approximately 220 seeds. Approximately 150 g may be needed to transplant 1 ha
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ceous crop such as tomato, eggplant, or potato. A preceding paddy rice crop is often helpful in that the flooded soil is depleted of many soil-borne pathogens and weed seeds. Addition of compost, animal manures, or green manures can boost the soil’s organic matter content and improve the soil’s nutrient buffering capacity. The soil should be loosened as deeply as practical, and fitted into beds according to local practices. Raised bed plantings are especially useful during raining periods; they improve the aeration of the pepper’s roots and minimize losses due to root diseases and flooding.
Transplant in the late afternoon or on a cloudy day to minimize transplant shock. Bury each plant to the level of the cotyledons or first true leaves and irrigate immediately to establish good root-to-soil contact. Transplanting can be done manually or by machine.
Fertilizing The amount of fertilizer to apply depends on soil fertility, fertilizer recovery rate, soil organic matter, soil mineralization of N, and soil leaching of N. A soil test is highly recommended to determine the available N, P, and K. The amount to be applied can then be calculated based on your target yield and adjusted for residual nutrients.
Transplanting Recommended spacing varies depending on cropping system, soil type, and variety. AVRDC uses 1.5-m wide beds (furrow to furrow), 30 cm high. We transplant two rows per bed. Rows are 55 cm apart, with 45 cm between plants within rows, for a plant population density of 29,630 plants/ha. Place three or four granules of carbofuran (Furadan 5G) in each hole just prior to transplanting to guard against the attack of cutworms and other insects. Under good conditions, seedlings are ready for transplanting four to five weeks after sowing. The ideal seedling has 4–5 true leaves, is disease-free, stocky, and has no flowers.
For example, if the target yield is 2.5 t/ha and the soil test indicates that 100 kg each of N, P, and K are available, you would need to apply about 125 kg N, 10 kg P, and 10 kg K. Nutrient requirements for a target yield of 5 t/ha (dry matter basis) are listed in Table 1. Forty percent of the N should be applied as basal fertilizer before transplanting. The remaining 60% should be side-dressed in three equal amounts at 2, 4, and 6 weeks after transplanting (WAT). Half of the P and K should be applied as basal fertilizer, and the remainder should be sidedressed at 4 WAT.
Bare-root seedlings are lifted from the seedbed by loosening the soil with a spading fork, and carefully separating the roots from the surrounding soil, discarding damaged or inferior plants, and binding into convenient bundles for transport to the field (Fig. 3). The seedlings should be kept cool, moist, and shaded between the lifting and transplanting tasks.
Fertilizer recommendations depend heavily on local conditions. Minor nutrient deficiencies, e.g. zinc, iron and calcium may also be factors in some localities. Consult your fertility management specialist for recommendations or conduct your own fertilizer trials to determine optimum rates. Table 1. N,P, and K requirements, expected recovery rate, and total amount to apply for a target yield of 5 t/ha of dried chili peppers Nutrient requirement (kg/ha)
Nutrient recovery (%)
Amount neededz (kg/ha)
N
180
40
450
P
22
10
220
K
200
50
400
Nutrient
Fig. 3. Growers carefully remove bare root seedlings for transplanting (above); close-up of seedlings (right)
Assuming no nutrients are available in the soil; the actual amount of fertilizer applied should be adjusted downward based on the soil test results. z
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Mulching
Controlling weeds
Mulching is recommended to reduce weed competition, soil compaction, and soil erosion. Mulching also maintains a uniform root environment and conserves soil moisture. Use rice straw (5 t/ha) or other organic material, polyethylene plastic, or a combination of materials.
If mulch is not available, or does not provide adequate weed control, several herbicides are available, such as Lasso (alachlor 43EC), Amex (butralin 47EC), Devrinol (napropamide 2E or 10G), and Dual (metolachlor 8E or 25G). Manual weeding can be performed as needed. At AVRDC, we spray 0.4% (v/v) Lasso 43EC at the base of the plants 2–3 days after transplanting, and then spray Roundup (glyphosate) to control weeds in the furrows later in the season. Care must be taken that Roundup does not drift to the pepper plants. The best herbicide, rate, and method of application will vary depending on weed species, soil type, and temperature at time of application. Consult with your local extension office for their recommendations.
Plastic mulch must be laid down before transplanting (Fig. 4); organic mulches can be laid down before or after transplanting. If plastic mulch is used, holes are cut in the plastic and plants are set directly into the holes. Reflective mulches will build up less heat in the soil than black plastic mulch and also provide some protection from aphids. During hot weather (>25°C nighttime temperature), cover plastic mulch with straw to reduce temperature in the root zone, or irrigate and drain the field frequently to keep temperatures down.
Staking Plants may be staked to prevent lodging, particularly when they have a heavy load of fruits. Each plant is individually staked before flowering stage (Fig. 5). Yields are generally higher with staking. Other staking and training techniques may be used based on local experience.
Fig. 4. Raised beds are formed and plastic mulch is laid in preparation for planting
Irrigating Pepper plants are fairly shallow-rooted and have low tolerance to drought or flooding. Fields should be irrigated if there are signs of wilting at midday. Thorough irrigation provides uniform soil moisture, essential for optimum plant and fruit growth. Furrow or drip irrigation are recommended; overhead irrigation should be avoided as wet leaves and fruits promote disease development. If overhead irrigation must be used, apply early in the day so that leaves are dry before nightfall.
Fig. 5. Staked planting
Controlling diseases General recommendations Use high quality, pathogen-free seeds and/or seedlings, and remove diseased leaves and seedlings promptly. Control weeds regularly. If you have a disease outbreak in one part of the field, work in other areas of the field before working in the diseased area. To restrict the spread of tobamoviruses, dip your hands and tools in milk before handling pepper plants. Be aware that irrigation water can carry pathogens, such as Phytophthora capsici.
Pepper plants cannot tolerate flooding and fields should be drained quickly after heavy rain. Pepper plants will generally wilt and die if they stand in water for more than 48 hours. Phytophtora blight and bacterial wilt may cause total crop loss following prolonged flooding.
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Use resistant cultivars, if available. If no resistant cultivar is available, try sowing the crop when pathogen pressure is lowest, and use the proper plant density, both in seedling production beds and in the transplanted field. High plant densities lead to weak plants, which are more susceptible to diseases.
Bacterial spot (Xanthomonas campestris pv. vesicatoria) Small watersoaked spots on leaves become necrotic with yellow borders (Fig. 7a). The lesions may be sunken on the upper surface and raised on the lower surface. Heavily infected leaves may turn yellow and drop, resulting in severe defoliation. Dark, raised lesions have a corky or wart-like appearance on fruits (Fig. 7b). Elongated necrotic spots or streaks appear on stems and petioles. This disease is seedborne and can survive in crop debris from infected plants. Many strains attack both tomato and pepper. The disease is enhanced by overhead watering, heavy dew formation, and high temperatures.
Prevent plants from being overloaded with fruits. Remove routinely all fruits that set at the first bifurcation node, and all leaves and branches below the first bifurcation node. This will promote vigorous plant growth and reduce the spread of foliar diseases. Crop rotation, particularly a rice–pepper rotation, helps reduce disease and insect problems. Peppers should never follow other Solanaceous crops, such as potato (Solanum tuberosum) or tomato (Lycopersicon esculentum), because these crops share many soil-borne diseases. Do not plant peppers after sweet potatoes (Ipomea batatas), due to allelopathic effects. The following are some of the most common diseases on chili pepper:
To control this disease, rotate pepper with cereals and other non-susceptible crops. Use pathogenfree seed and transplants. Resistant cultivars are becoming available, but may not be resistant to all strains of the disease. Sprays of copper or copper + maneb will reduce damage. Rain shelters may reduce the severity of disease during rainy periods.
Anthracnose (Collectotrichum spp.) Anthracnose may occur in the field or develop as a post-harvest decay of pepper fruits. Typically, symptoms first appear on mature fruits as small, watersoaked, sunken lesions that rapidly expand. The lesions may increase to 3–4 cm in diameter on large fruits (Fig. 6). Fully expanded lesions are sunken and range from dark red to light tan. The disease may occur wherever pepper is grown under overhead irrigation or rainfed conditions. The pathogens can be seed-borne in pepper and persist in crop debris. They have a wide host range.
Fig.7. Bacterial spot lesions on leaf and fruit
To control anthracnose, use pathogen-free seed and rotate crops. Fungicides can reduce losses. Since symptoms usually occur on mature fruit, harvest and utilize fruit in the immature green stage, or harvest mature fruit frequently and process quickly.
Bacterial wilt (Ralstonia solanacearum) The initial symptom is wilting of lower leaves (or upper leaves of seedlings) followed by a sudden and permanent wilt of the entire plant without yellowing (Fig. 8a). Vascular browning occurs (Fig. 8b) and cortical decay is sometimes evident near the soil line. Bacterial streaming from vascular elements occurs when cross sections of the lower stem are suspended in water. The disease affects over 200 different plant species. It is more severe on tomato, tobacco, potato and eggplant, but it can be very damaging to pepper. The bacterium survives in the soil for long periods. It gains entry through natural root wounds or wounds created by insects, nematodes or cultivation. High temperature and high soil moisture favor disease development.
Fig. 6. Anthracnose lesions on mature fruit
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This soil-borne disease is controlled through the use of resistant cultivars, raised beds, crop rotation, and fungicides such as mefenoxan, metalayxl, potassium phosphate, copper alone, or copper-containing products. To avoid soil splash, the use of mulch and furrow irrigation, rather than overhead irrigation, are preferred.
To control bacterial wilt, use pathogen-free seedbeds to produce disease-free transplants. Fumigate seedbeds and pasteurize the planting medium for container-grown plants. Rotate with flooded rice; rotation with non-susceptible crops provides limited value. Avoid cultivation that damages roots. Use raised beds to facilitate drainage. Resistant cultivars are being developed.
I Fig. 10. Phytophthora lesion; healthy and blightinfested seedlings
Fig. 8. Healthy and bacterial wilt-infected plant; browning of inner vascular tissue
Aphid-transmitted viruses: Chili veinal mottle virus (ChiVMV), cucumber mosaic virus (CMV), potato virus Y (PVY)
Cercospora leaf spot (Cercospora capsici) Its "frog eye" leaf lesions are circular, about 1-cm in diameter, with brown borders and light gray centers (Fig. 9). Severe infection can cause leaf drop, with or without leaf yellowing. Lesions also appear on stems, petioles and peduncles; fruit do not beFig. 9. Cercospora come infected. The fungus "frog eye" lesions survives from one season to another on crop debris. Extended rainy periods and close plant spacing enhance development. Fungicides are usually only necessary during conditions highly favorable to the disease.
Symptoms vary, but generally these diseases show mosaic, mottled and/or deformed leaves (Fig. 11). Plants are stunted and the loss of marketable yield can be dramatic. To control, use resistant cultivars. Reduce the number of aphid vectors by controlling weeds, using insecticides, and using mesh netting to exclude aphids from seedlings.
Phytophthora blight (Phytophthora capsici) This disease can occur on pepper grown anywhere in the world, at any stage of growth, and on all plant parts. The most common symptom is a stem or collar rot followed by sudden wilting without foliar yellowing (Fig. 10a). Other symptoms include damping-off and tip blight of young seedlings (Fig. 10b), dried tan-colored lesions on foliage, as well as softened fruit.
Fig.11. Mottling of leaves caused by PVY and ChiVMV, respectively.
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Tobamoviruses: Tobacco mosaic virus (TMV), tomato mosaic virus (ToMV); and potato mild mottle virus (PMMV) These diseases are transmitted in and on seeds, as well as through contact of plants. Symptoms include stunting, leaf mosaic and crinkling (Fig. 12), and systemic Fig. 12. Leaf crinkling bleaching of leaves. To caused by PMMV minimize problems, use resistant varieties and pathogen-free seeds. Dip tools in milk or TSP before handling plants.
Fig. 13. Aphids (inset right) cause sooty mold and leaf distortion
Broad mite (Polyphagotarsonemus latus) This tiny, crab-like pest (Fig. 14) causes leaves to curl downwards and become narrow. Most damage occurs between veins of young leaves. Corky tissue develops on fruits. Mites are yellow or white, tiny (about the size of a grain of sand), and found near the mid-vein on the undersides of the leaves.
Controlling insect pests General recommendations Seedlings in the nursery can be protected using mesh netting or yellow sticky traps. After plants are in the field, scout plants at least twice a week, looking for damage. Plant extracts, such as neem seed or hot pepper extract, can be sprayed on seedlings to help protect them.
This pest is controlled through the use of tolerant cultivars, weed control, crop rotation, and miticides such as abamectin and dicofol.
Chemical pesticides should be used mainly as a corrective measure. If possible, choose a pesticide that targets the specific pest that is causing the damage, and avoid pesticides that kill beneficial organisms. Choose pesticides that have short persistence, i.e., the effects of which last only a few days. Chemical pesticides should be applied in the evening, and workers should not be allowed into the field until the recommended waiting period (usually 12 or 24 hours) has passed. Wear protective clothing and follow label directions. If multiple applications are needed, rotate pesticides that have different modes-of-action.
Fig. 14. Mites (inset right) cause leaves to curl downwards and corky tissue to develop on fruits
Aphids (Aphis gossypii, Myzus persicae)
Thrips (Scirtothrips dorsalis, Thrips palmi)
These are small, succulent, pear-shaped insects that vary in color from yellow to green to black (Fig. 13). Aphids pierce leaves and suck the sap, causing foliage to become distorted and often curled under. Aphids exude a sticky substance that attracts ants and leads to the development of a sooty mold on plants. Aphids are vectors to many viruses, including ChiVMV, CMV and PVY. Control aphids by using reflective mulches, rotating crops, spraying with pesticides, or introducing predators and parasites.
Thrips cause young leaves to curl upwards (Fig. 15a). Brown areas develop between veins of both young and old leaves. Corky tissue develops on infested fruits. Thrips are very small and group together along the mid-vein (Fig. 15b) or along borders of damaged leaf tissues. Reduce thrip damage by controlling weeds, rotating crops, using predators and parasites, and rotating insecticides.
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peratures and light sandy soils are conducive for its development. To control, use crop rotation; flooded rice in particular greatly reduces nematode populations. A few resistant cultivars are available. Soil fumigants or nematicides may be used. Plowing during the fallow season will expose nematodes to drying and eliminate weeds that host the pest.
Harvesting For fresh use, chili peppers can be harvested either at the green immature or red mature stage. It takes about 55–60 days after flowering for fruits to fully ripen, depending on temperature, soil fertility, and cultivar. Warmer temperatures will hasten ripening, and cooler temperatures will delay ripening. If conditions are favorable, chili production can continue for several months. Fruits can be harvested weekly.
Fig. 15. Thrips cause leaves to curl upwards; they are often found near the mid-vein of leaves.
Tomato fruitworm (Helicoverpa armigera) Tomato fruitworm feeds on flowers, pods and fruits of pepper (Fig. 16). Larvae move from one fruit to the next, destroying only small portions of each fruit. Damaged fruits may drop, ripen prematurely, or become infected with disease. The entrance hole near the pedicel develops a dark scar. Monitor closely, looking for the larvae on plants; older larvae can be found by cutting into fruits. Young larvae are light yellow and spotted. Mature larvae are brown to gray in color with lengthwise stripes along the body. To control, spray insecticides to kill exposed larvae. Remove infested fruits to reduce pest populations.
Fresh chili fruits should not be washed unless they will be kept cool (10°C) until sold. Fruits should be stored in a cool, shaded, dry place until they are sold. At typical tropical ambient temperature and humidity (28°C and 60% RH), fruits will last unspoiled for 1–2 weeks. Anthracnose is the major cause of fresh fruit spoilage. For dry chili, it's important to preserve the red color of the mature fruits. Drying them in the sun is a common practice (Fig. 18), but this tends to bleach the fruits, and rainfall and dew promote fruit rot. Solar dryers have been developed, but they reFig. 18. Peppers drying quire fairly constant in the sun sunshine. Cloudy weather increases the drying time and the risk of post-harvest spoilage. Blanching the fruits in hot water (65°C) for 3 minutes and removing the pedicel and calyx can decrease drying time, increase color retention, and reduce post-harvest losses. In general, cultivars with low dry matter content and/or thick flesh are difficult to dry and are generally sold fresh. If ovens are available, dry fruits for 8 hours at 60°C, then reduce the temperature to 50°C and continue until fruits are completely dry (about 10 more hours).
Fig. 16. Fruitworm larva boring inside pepper
Other disorder Root-knot nematode (Meloidogyne incognita and other Meloidogyne spp.) This nematode damages the root system. Infested plants become stunted and yellowed. Severely affected plants may wilt. A careful look at the root system will reveal small galls (Fig. 17). This nematode has a very wide host range. Its eggs can remain dormant for a few months. Warm tem-
In temperate regions, harvesting is usually halted by frost. In tropical and subtropical regions, production declines due to disease or other stresses.
Fig. 17. Knotted, galled pepper root system
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FACT SHEET Agriculture and Natural Resources
PP401.04
This is the fourth fact sheet in a series of ten designed to provide an overview of key concepts in plant pathology. Plant pathology is the study of plant disease including the reasons why plants get sick and how to control or manage healthy plants.
Keeping Plants Healthy
An Overview of Integrated Plant Health Management Sarah D. Ellis Michael J. Boehm Department of Plant Pathology
Integrated Plant Health Management (IPHM)
Regardless if managing a weed, insect pest, or diseasecausing organism, most specialists interested in plant health recommend the use of a multi-pronged approach or strategy commonly referred to as an Integrated Pest Management or an Integrated Plant Health Management approach. Integrated Plant Health Management programs rely on the use of several methods rather than on a single means for avoiding or otherwise minimizing the impact of plant pests and pathogens. Although sometimes called different names by weed scientists, entomologists, and plant pathologists, the methods for managing or eliminating plant pests fall into five categories. 1. Genetic Host Resistance—the use of genetically resistant plants to minimize or avoid losses caused by insect pests and/or pathogens. The use of genetically resistant plants is often recommended by entomologists and plant pathologists as the first line of defense for avoiding or minimizing plant damage caused by insects and pathogens. In some cropping systems, such as large acreage field or row crop agriculture (corn, soybeans, wheat, rice, cotton, etc.), the use of genetically resistant plants may be the only cost-effective means for managing a particular pest or disease. In some cases, the use of resistant cultivars or varieties might be the only means of effectively managing a disease or pest such as in the case of managing plant diseases caused by viruses. The development of resistant plant types may also reduce the need for using pesticides. Although genetic resistance should be considered when dealing
with all insect pests and diseases, it is especially useful when dealing with annual cropping systems where new seed is sown each season thereby providing an opportunity to introduce new cultivars or varieties with insect or pathogen resistance. Although important in perennial cropping systems such as orchards, forests, golf courses, or home lawns, once the initial crop is planted, the introduction of resistant lines is limited due to the long-term nature of these crops. 2. Cultural Practices—the use of agronomic or horticultural practices which favor plant development and minimize pest or pathogen activity. There are a number of cultural practices that can be used to change the environment in which plants are grown that can severely influence pest and pathogen activity, These practices include tillage practices, water management, fertility, crop rotation, and sanitation (cleaning or removal) of equipment and diseased or infested plant material. Cultural practices designed to achieve or maintain disease play a key role in reducing plant losses by minimizing or eliminating sources of insect pests, weed seed, or pathogen inoculum. Practices such as the removal and destruction of infected plants or infested soil or potting mix, and the use of “certified” pathogen-free or weed-free seed as well as the use of “clean” tools and equipment are critical to maintaining healthy plants and reducing spread of weeds, insects, and pathogens. 3. Chemical Applications—the use of pesticides such as herbicides (weeds), insecticides (insect pests), fungicides (fungi), and nematicides (nematodes) to suppress
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