|
PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
Rice (Oryza sativa) productivity is adversely impacted by numerous biotic and abiotic factors. An approximate 52% of the global production of rice is lost annually owing to the damage caused by biotic factors, of which ~21% is attributed to the attack of insect pests. We have developed transgenic pyramided rice lines, endowed with enhanced resistance to major sap sucking insects, through sexual crosses made between two stable transgenic rice lines containing Allium sativum (ASAL) and Galanthus nivalis (GNA) lectin genes. Presence and expression of asal and gna genes in pyramided lines were conï¬Ârmed by PCR and western blot analyses. Segregation analysis of F2 disclosed digenic (9:3:3:1) inheritance of the transgenes. Homozygous F3 progenies plants carrying asal and gna genes were identiï¬Âed employing genetic and molecular methods besides insect bioassays. Pyramided lines, infested with brown plant hopper (BPH), proved more effective in reducing insect survival, fecundity, feeding ability besides delayed development of insects as compared to the parental transgenics. Under infested conditions, pyramided lines were found superior to the both the parental transgenics in their seed yield potential. This study also reveals the feeding behavior of the BPH insects on both the pyramided as well as parental transgenic lines and the effect of mannose specific lectins asal and gna under the control of different promoters CaMV35S and Rss1 on the feeding behavior of BPH. BPH insects fed on GNA transgenic plants showed phloem specific feeding up to 72 h and later switched over to xylem feeding after 72 h. In contrast, BPH insects fed on ASAL transgenic rice plants did not show any difference in the feeding behavior even after 96h. The pyramided lines appear promising and might serve as a novel genetic resource in rice breeding aimed at durable and broad based resistance against hoppers.