Evaluation of The Tolerance Levels of 35 Cacao Genotypes to Dry Periods

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A prolong dry periods could have a negative impact on growth and yield of cocoa. The objectives of this study were to evaluate the tolerance levels of 35 cocoa genotypes to dry periods. The study was conducted at the Pakuwon Experimental Station, Indonesian Industrial and Beverages Crops Research Institute, Sukabumi, West Java; 450 m above sea level; Latosol soil type; and B type of climate; started from August 2014 until October 2015. Thirty five cacao genotypes consisted of two released variety  (i.e Sulawesi 1 and SCA 6) and 33 other genotypes were used in this research.  The cacao plants were three-years old, cultivated at a 3 x 3 m spacing distance under the 26 years old Salak Dwarf coconut trees.  Ten plant samples were determined randomly and the fruits were harvested in February 2015 (wet period) and October 2015 (dry period). A bulk of 10–30 pods per genotype were randomly selected for each harvest periods. The variable observed were fresh weigth per pod,  number of beans per pod, fresh and dry weight of beans per pod, and fresh weight of pod husks + pulps per pod. The tolerance level to dry periods was determined base on the dry weight of bean/pod.  The result showed that a continueous six months dry periods prior to harvesting significantly reduced yield components from 4.92%-42.54%.  Based on the dry weight of beans per pod, three genotypes, namely KW 162, KW 165, and KW 215, were classified as tolerant, while the other were moderately tolerant and susceptible to drought. The result implies the important of further research to obtain superior cocoa clones resistance to drought.
Periode kering yang panjang akan berdampak negatif terhadap pertumbuhan dan hasil kakao. Penelitian bertujuan mengetahui tingkat toleransi 35 genotipe kakao terhadap periode kering. Penelitian dilakukan di KP. Pakuwon, Balai Penelitian Tanaman Industri dan Penyegar, Sukabumi, Jawa Barat; ketinggian tempat 450 m dpl; jenis tanah Latosol; dan tipe iklim B; mulai Agustus 2014 sampai Oktober 2015. Tiga puluh lima genotipe kakao, terdiri atas dua genotipe unggul Sulawesi 1 dan SCA 6 serta 33 genotipe lokal digunakan dalam penelitian. Tanaman kakao berumur 3 tahun, ditanam pada jarak tanam 3 m x 3 m di bawah pohon penaung kelapa Genjah Salak umur 26 tahun. Sepuluh pohon contoh dipilih secara acak; buah dipanen pada bulan Februari 2015 untuk periode basah dan Oktober 2015 untuk periode kering, berdasarkan data curah hujan dan hari hujan. Sebanyak 10–30 contoh buah per genotipe dipilih secara acak dari populasi komposit untuk masing-masing periode panen. Peubah yang diamati adalah bobot segar/buah,  jumlah biji/buah, bobot segar dan kering biji/buah, serta bobot segar kulit buah + pulp/buah.  Tingkat toleransi tanaman kakao terhadap periode kering didasarkan pada peubah bobot kering biji/buah. Hasil penelitian menunjukkan periode kering selama enam bulan sebelum panen berdampak nyata terhadap penurunan komponen buah kakao sebesar 4,92%‒42,54%. Berdasarkan karakter bobot kering biji/buah, tiga genotipe kakao, yaitu KW 163, KW 165, dan KW 215, dapat dikelompokkan ke dalam genotipe toleran kekeringan, sedangkan genotipe lain termasuk ke dalam kelompok yang cukup toleran dan rentan. Hasil penelitian menunjukkan perlunya penelitian berikutnya untuk merakit varietas unggul kakao tahan kekeringan.
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