PEWARISAN SIFAT HERMAPRODIT DAN KONTRIBUSINYA TERHADAP DAYA HASIL PADA JARAK PAGAR (Jatropha curcas L.)
Authors: HARTATI RR. SRI , SUDARSONO SUDARSONO 
Published: June 2020

<p>ABSTRAK<br />Kontribusi sifat hermaprodit terhadap daya hasil tanaman jarak<br />pagar belum banyak diketahui. Tujuan penelitian adalah mengetahui peran<br />bunga hermaprodit terhadap daya hasil dan mekanisme pewarisannya.<br />Penelitian dilakukan terhadap 60 genotipe jarak pagar di Kebun Percobaan<br />Balittri Sukabumi. Penelitian dilaksanakan mulai bulan Mei 2007 sampai<br />dengan Juli 2010. Jarak tanam 2 m x 2 m, menggunakan 2,5 kg pupuk<br />kandang + 20 g Urea + 20 g SP 36 + 10 g KCl per tanaman. Penelitian<br />terdiri dari (1) evaluasi tipe bunga jarak pagar dan (2) pewarisan sifat<br />hermaprodit dan kontribusinya terhadap daya hasil. Hasil evaluasi<br />menunjukkan bahwa delapan dari 60 genotipe jarak pagar yang dievaluasi<br />merupakan tanaman tri-monoecious yang menghasilkan bunga jantan,<br />bunga betina, dan bunga hermaprodit, 52 lainnya merupakan tanaman<br />monoecious yang hanya menghasilkan bunga jantan dan bunga betina.<br />Karakter yang dimiliki oleh delapan genotipe tri-monoecious yang<br />dievaluasi adalah lebih lambat berbunga (mulai berbunga pada umur 120-<br />274 hari) dan berdaya hasil rendah sampai sedang (jumlah buah 23-228<br />per tanaman pada tahun pertama). Kemunculan bunga hermaprodit tidak<br />terjadi sepanjang tahun, tetapi lebih dominan pada tanaman berumur enam<br />bulan. Persentase bunga hermaprodit berkisar 6,25-53% dari total bunga<br />yang dihasilkan. Persentase fruitset pada tandan bunga hermaprodit lebih<br />tinggi dibanding tandan bunga non-hermaprodit, dengan tingkat<br />keberhasilan rata-rata 80% (kisaran 56-100%). Pada tandan bunga yang<br />tidak menghasilkan bunga hermaprodit, buah jadi rata-rata sebesar 50%<br />(kisaran 11-100%). Daya hasil tanaman jarak pagar ditentukan oleh<br />genetik tetua. Bunga hermaprodit diwariskan oleh tetua betina maupun<br />tetua jantan. Gen pengendali sifat hermaprodit diduga adalah gen<br />sederhana yang bersifat dominan.<br />Kata kunci: Jatropha  curcas,  monoecious,  tri-monoecious,  bunga<br />hermaprodit, fruit set</p><p>ABSTRACT<br />Hermaphrodite character has been reported in physic nut, its role<br />and contribution to production process especially to the yield has not been<br />investigated. The objectives of this research were to evaluate<br />hermaphrodite flowers contribution on yield and their mechanism<br />inheritance. The evaluation was conducted at the Experimental Station of<br />Balittri Sukabumi from May 2007 to July 2010. The spacing was 2 m x 2<br />m with 2,5 kg manure + 20 g Urea + 20 g SP 36 + 10 g KCl/plant. The<br />experiment consisted of (1) evaluation of flower type of physic nut and<br />(2) hermaphrodite inheritance and their contribution on yield. Results of<br />the experiment indicated eight from 60 physic nut genotypes were tri-<br />monoecious which were capable on producing male, female, and<br />hermaphrodite flowers while as the rest (52 genotypes) were monoecious<br />which produced only male and female flowers. The tri-monoecious were<br />generally late flowering (120-274 days after planting) and low to medium<br />yield (producing 23-228 fruits per plant in the first year). Hermaphrodite<br />flowers generally occurred six months after planting at the amount ranged<br />from 6,25-53% of total flowers. Fruit set of inflorescences having<br />hermaphrodite flowers was higher, average of 80% (ranged from 56-<br />100%) than those with female and male flowers, average of 50% (ranged<br />from 11-100%). Yield of physic nut was affected by the genetic potential<br />of their parents rather than hermaphrodite character. Hermaphrodite flower<br />character was inherited by both female and male parents and might be<br />controlled by simple-dominant gene.<br />Key words: Jatropha curcas, monoecious, tri-monoecious, hermaphrodite<br />flower, fruit set</p>