Collection, evaluation, characterization, maintenance and utilization of castor germplasm 2013

Abstract

Augmentation, characterization and evaluation of castor germplasm: Added 12 new accessions collected from Gujarat and Maharashtra to castor repository. Characterized 217 new accessions for 23 descriptors and evaluated for 19 quantitative traits. Forty seven accessions were identified for various traits viz., 3 accessions for short plant height (9-23cm), 7 for low node number (6-10), 10 accessions for long primary raceme (53-67 cm), 8 for long length of primary raceme covered by capsules (50-66cm), one for broad width of primary raceme (10 cm), 2 for early flowering (50-51 days), 5 for early maturity (88-89 days), 3 for high number of productive racemes/plant (17-19) and 18 for high seed weight (35-48g/100 seeds). In addition, 6 accessions possessing high seed yielding capacity at 120 days after planting (87-92 g/plant) and 6 at 150 days planting (65-71g/plant), 8 having high seed yielding capacity at 180 days after planting (35-38 g/plant), one recording high seed yield at 210 days after planting (45g/plant) and 4 accessions viz., RG3488, RG3497,RG3508,RG3511 possessing high total plot seed yield (14.13-15.31kg/plot) were identified under rainfed conditions.

Multiplication, documentation, conservation and supply of germplasm

A total 622 accessions were multiplied. Passport information and data on morphological and quantitative traits of 217 fresh accessions were documented. Conserved 3331 accessions of castor germplasm under ambient conditions. Supplied 760 accessions to various AICRP (Castor) centres for multilocation yield evaluation and screening against diseases and insect pests besides 626 accessions for research purpose to various castor researchers in the country. Sources of resistance to diseases and insect pests Wilt: Wilt resistance was confirmed in three accessions viz., RG558 (IC432945), RG2781 (IC346585) and RG3020 (EC501586) using root-dip inoculation method. Six accessions viz., RG386 (IC432910), RG404, RG479, RG926, RG2746 and RG2976 were found free from wilt (0% wilt incidence) while 20 exhibited resistance reaction (< 20% wilt incidence) in wilt sick plot. Botrytis grey rot: Resistance reaction against grey rot was confirmed in three accessions viz., RG907 (<10% disease), RG1139 (IC373962) (<20% disease) and RG3216 (IC47272) (<20% disease) under artificial epiphytotic conditions in the field and greenhouse.

Leafhopper: Resistance against leafhopper was confirmed in RG631 and RG2469 in the second consecutive year with zero hopper burn and 12-13 leafhoppers/ three leaves/plant.

Capsule borer: Resistance reaction against capsule borer of two accessions, RG2980 and RG2774 (IC374330) was confirmed (11.8% damage) under artificial infestation.

Registration of germplasm Submitted registration proposal of RG19/EC168752 (Extra-early maturity), RG2818/IC346622 (wilt resistant) and RG 2822/IC346626 (root rot resistant) to Institute’s Germplasm Identification Committee (IGIC) on 30 June 2012, approval of Chairman of IGIC is awaiting for forwarding it to Plant Germplasm Registration Committee, NBPGR, ICAR.

Stabilization of non-TSP-10R pistillate lines Two non-TSP-10R pistillate lines developed from wild germplasm accessions were stabilized for pistilateness. All the spikes in these lines have stably expressed pistillateness; these were multiplied by using pollen from interspersed staminate flowers that developed on tertiary and quaternary order spikes.