Mass Rearing Of Chilo Spp. On Artificial Diets And Its Use In Resistance Screening

Several species of Chilo are serious pests of cereal crops. The important species attacking cereals are Chilo agamemnon, C. orichalcociliellus and C. parrrllus on malze and sorghum; C. auricilius and C. zacconius on sugar-cane, and rice; C. suppressalis on rice; and C. sacchariphagus indicus on sugar-cane. Insects are reared In the laboratory on natural and artificial diets for various purposes, namely for insecticide testing, hormone and pheromone manipulation, biological control, host-plant resistance, etc. Rearing of an insect In the laboratory requires rearing facilities, colony establishment, research and development of rearing techhiques, resources, and maintenance of insect quality. All these aspects for rearing major Chilo spp. have been discussed. However, detailed information is available only for C. partellusand C.supprersalis. Techniques used for resistance screening anddamageevaluation against spotted stem borer, C. partellus using naturally occurring populatlon and artificial infestation are described

Chemical control of sorghum shoot fly: dosage, method and frequency of insecticide application in India

Experiments in resistant and susceptible sorghum genotypes during the post-rainy season from 1986 to 1988 at ICRISAT, India showed that foliar applications of cypermethrin applied by ‘Electrodyn’ sprayer were significantly superior to high-volume and low-volume sprays. Effective control of shoot fly and higher grain yields were obtained when the spray was initiated 6 days after crop emergence. The lowest dosage of cypermethrin (22.5 g a.i. ha−1) gave shoot fly control and grain yield increases similar to those of the higher dosages (33.75 and 45 g a.i. ha−1). Chemical control of shoot fly had the greatest effect on shoot fly infestation and increases in grain yields in susceptible genotype CSH 1, followed by the local M35-1 and resistant ICSV 707. Cypermethrin applied by Electrodyn was significantly superior to the recommended practice of carbofuran soil application and high-volume spray of endosulfan in reducing shoot fly damage in all the three genotypes. The main effect of cypermethrin foliar application was in the reduction of shoot fly oviposition that resulted in less damage, indicating either an oviposition deterrent effect or death of the adults before oviposition

Assessment of Yield Loss of Sorghum and Pearl Millet due to Stem Borer Damage

The stem borer species that infest sorghum and pearl millet are listed. At ICRISAT Center in India, loss in grain yield due to Chilo partellus damage in sorghum was estimated by two methods. These experiments involving the phased use of carbofuran, or artificial infestation using laboratory-reared first instar larvae showed that maximum grain yield loss occurred when infestation took place 15-30 days after crop emergence. The maximum number of deadhearts was formed when infestation took place during this period. Stem tunneling caused by later infestations did not cause a reduction in grain yield. In two studies at the ICRISAT Sahelian Center in Niger, results showed that under low levels of borer infestation (caused by Coniesta ignefusalis), a nonprotected pearl millet crop gave slightly higher yields than one that was protected by insecticide. In a date of sowing trial, losses were heavier on late-sown millet with an increase in proportion of nonproductive tillers. Yield loss caused by other borer species are also discussed

Host-plant resistance to sorghum stem borer

Sorghum is an important cereal crop in the semi-arid tropics. In India it is grown during the rainy (Kharif) and the post rainy (rabi) seasons Grain yields under farmers conditions are generally low (500-800kg ha-1)one of the reasons for low yields is crop damage by insect pest. Nearly 150 insects species have been reported on sorghum (young and teetes 1977 Seshureddy and Davies 1979 b)of which most widespread and economically important pests are shoot fly stem borers, army worm, midge, head bugs, and head caterpillar

The Role Of Host-Plant Resistance In Pest Management In Sorghum In India

The sorghum agroecosystem in India has been destabilized by the introduction of new varieties and hybrids that are not resistant to major pests such as Atherigona soccata, Chilo partellus, Contarinia sorghicola and Calocoris angustatus. An integrated pest management system needs to be developed, based on traditional pest management practices, of which pest resistance, cultural control and biological control were important components. For a better understanding of such a control approach, the biology of the major pests is summarized and a brief account of levels and mechanisms of pest resistance known so far in sorghum is provided. Based on this information, the rainfall pattern, plant duration to maturity, time of planting, natural enemies and insecticides, a sorghum-based integrated pest management system is proposed for the monsoon and post-monsoon season, in which host-plant resistance may be used alone or in combination with other control measures

On the A-dependence of nuclear generalized parton distributions

We perform a microscopic evaluation of nuclear GPDs for spin-0 nuclei in the framework of the Walecka model. We demonstrate that the meson (non-nucleon) degrees of freedom dramatically influence nuclear GPDs, which is revealed in the non-trivial and unexpected A-dependence of DVCS observables. In particular, we find that the first moment of the nuclear D-term, d_A(0) ~ A^2.26, which confirms the earlier prediction of M.Polyakov. We find that in the HERMES kinematics, contrary to the free proton case, the nuclear meson degrees of freedom in large nuclei enhance the nuclear DVCS amplitude which becomes comparable to the Bethe-Heitler amplitude, and, thus, give the non-trivial A-dependence to the DVCS asymmetries: as a function of the atomic number the beam-charge asymmetry increases whereas the beam-spin asymmetry decreases slowly.Comment: Final version published in J. Phys. G. 17 pages, 9 figure

Breeding for resistance to Chilo partellus Swinhoe in sorghum

Host-plant resistance plays an important role in the insect-pest management either alone or in combination with other control methods. A number of sorghum genotypes showing varying levels of resistance to spotted stem borer, Chilo partellus Swinhoe have been identified using natural and artificial infestations. Major resistance mechanisms are antibiosis and tolerance, though some genotypes exhibit ovipositional non-preferences. There have been a number of factors involved in spotted stem borer resistance; a resistant genotype possesses either one or a combination of these traits. Progress has been made in developing borer resistant breeding lines with moderate yield and acceptable grain quality. Borer resistance is a quantitatively inherited trait governed by additive and non-additive genes. Epistatic gene effects are more pronounced under artificial borer infestation. Cytoplasmic effects appear to be presen