رسائل ماجيستير
English
2003
The Susceptibility of Some Wheat Grain Varieties to Trogoderma granarium Everts Attack
El-Imam El-Khidir, Hassbelrasul Ahmed Mohamed
كلية الزراعة-جامعة الخرطوم · السودان
A laboratory study was carried out, in the Faculty of Agriculture at Shambat, to determine the susceptibility of some varieties of wheat, stored for six months under room conditions, to Trogoderma granarium attack. On the basis of the percentage of damage seeds, loss percentage in weight and the population build-up, the variety Debeira was markedly affected indicating high susceptibility followed by Elnilein then Vee/PJN112 which was considered as the least susceptible. However, the variety Condor was found completely free from damage and there was neither loss in weight nor any development of Trogoderma, hence it was considered as resistant. At the end of the experimental period the percentage of damaged seeds was 39.5%, 26.0%, 7.5% and (zero) for Debeira, Elnilein, Vee/PJN112 and Condor, respectively, while the percentage loss in weight was 13.87%, 8.61%, 1.60 and (zero) for them respectively. The percentage of dust was high in Debeira (2.18%) followed by Elnilein (1.49%) then Vee/PJN112 (0.09%). The study revealed that the hardness of the grain has a negative relation with the susceptibility of the varieties tested. The germination capacity at the end of storage period was highly (significant) decreased in infested grains of Debeira (62%), Elnilein (72%) and Vee/PJN112 (90.7%), compared to uninfested grains which were not affected (100%). However, in variety Condor the germination capacity was not affected (100%). Concerning the feeding activity of the test insect on the same varieties, the highest feeding activity occurred in the second period (April/May) and the lowest in the first period (Jan./Feb.). Among the four varieties, in both periods, the highest feeding activity was observed on Debeira followed by Elnilein then Vee/PJN122. However, in Condor the larvae were completely unable to feed.