Morpho-physiological traits and leaf surface chemicals as markers conferring resistance to sorghum shoot fly (Atherigona soccata Rondani)

Abstract

Sorghum shoot fly, Atherigona soccata,causes substantial economic losses in sorghum globally. Cultural practices and host plant resistance are effective measures for mitigating the losses caused by sorghum shoot fly. Therefore, we evaluated 32 sorghum genotypes consisting of a set of 10 restorer lines, 10 CMS (cytoplasmic male-sterile) lines and their respective maintainers exhibiting resistance/susceptibility to shoot fly along with resistant and susceptible checks under field conditions. The traits such as leaf glossiness, leaf sheath pigmentation, percentage plants with shoot fly deadhearts and number of shoot fly eggs per plant were used as morphological markers for selecting genotypes with resistance to shoot fly during the rainy and post rainy seasons of 2016 and 2017. The test material was also subjected to biochemical analysis (total soluble sugars, protein and tannin contents), while the leaf surface chemicals were analysed by GC-MS to identify the compounds associated with resistance/susceptibility to shoot fly. The genotypes differed significantly for all the traits, except percentage plants with shoot fly deadhearts during the 2016 rainy season. The genotypes ICSB 458, ICSA/B 467, ICSA/B 487, ICSA/B 14037, IS 18551 and ICSV 93046 exhibited moderate to high levels of resistance to shoot fly based on number of plants with shoot fly deadhearts, plants with shoot fly eggs and total number of shoot fly eggs. The shoot fly resistant genotypes ICSB 84, ICSA/B 467, ICSB 487, ICSB 14024, and IS 18551 had low shoot fly deadheart incidence, higher amounts of condensed tannins, soluble sugars, phenols and lower protein content as compared to the susceptible genotypes. Thirteen unique compounds were identified from leaf surface extracts by GC-MS which were associated with shoot fly resistance/susceptibility. While HPLC analysis revealed that Protocatechuic and coumaric acids were present in most of the sorghum genotypes, but their amounts were significantly greater in resistant as compared to the susceptible ones. The findings of the study highlight the importance of various morphological and biochemical traits conferring resistance to sorghum shoot fly, and these traits can be used as markers to identify shoot fly resistant genotypes for use in breeding programs.

Multi‐trait stability index for the identification of shoot fly (Atherigona soccata) resistant sorghum lines from a mini core collection

“…Based only on mean DH% over 3 years, lines IS 18551, IS 2205, IS 12697, IS 26222, IS 25732, IS 4631 were resistant (<44%–48% DH) while lines IS 31043, 296B, IS 23590, IS 33090 and IS 31651 were continually susceptible (69%–76% DH). IS 18551, IS 2205 are the stable resistant sources reported by earlier studies 23,24,37,49,50 . In the present study, IS12697 ( bicolor race from Australia), IS26222 ( Guinea‐caudatum from Togo), IS25732 ( durra from Mali), IS 4631 ( durra , India) were the new sources of resistance identified based on the lowest DH% over 3 years.…”

“…IS 18551, IS 2205 are the stable resistant sources reported by earlier studies. 23,24,37,49,50 In the present study, IS12697 (bicolor race from Australia), IS26222 (Guinea-caudatum from Togo), IS25732 (durra from Mali), IS 4631 (durra, India) were the new sources of resistance identified based on the lowest DH% over 3 years. IS 4631 was reported to be shoot fly resistant.…”

Molecular mechanisms, genetic mapping, and genome editing for insect pest resistance in field crops

“…The defensive leaf structures of the plant safeguards itself by the development of dense trichomes, spines, setae, as well as leafy toughness, cuticular thickness, and release of waxy epicuticles (Peterson et al 2016 ). In particular, morphological traits such as leaf glossiness, plant vigor, and leaf-sheath pigmentation are responsible for imparting resistance against Sorghum shoot fly, Atherigona soccata , in sorghum (Mohammed et al 2016 ; Arora et al 2021 ). In sweet corn, husk tightness showed significant resistance against corn ear worm, Helicoverpa zea (Cameron and Anderson 1966 ; Wiseman and Davis 1990 ).…”

Potential food applications of sorghum (Sorghum bicolor) and rapid screening methods of nutritional traits by spectroscopic platforms

“…The results of rapid screening methods can be further analyzed and validated to identify the inherited bio fingerprints of sorghum plants associated with nutritional traits (Arora et al, 2021). For example, the leaf surface area of wheat plants has been identified as a bio fingerprint to determine the leaf nitrogen content and the efficiency of photosynthetic nitrogen usage (Jia et al, 2021).…”