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Pigeonpea [Cajanus cajan(L.) Millsp.] is an important legume crop in South Asia, East and southern Africa, and the Caribbean. Pod fly (Melanagromyza obtusaMalloch) and pod wasp (Tanaostigmodes cajaninaeLa Salle) are important constraints to increase the production and productivity of pigeonpea under subsistence farming conditions. Host plant-resistance can be used as an important component for the management of these pests, and therefore, we evaluated 28 accessions of wild relatives of pigeonpea for resistance to these pests. There were significant inter- and intra-species differences in the relative susceptibility to pod fly and pod wasp damage. Accessions belonging to Cajanus scarabaeoides(L.) Thouars, C. sericeus(Benth. ex Bak.) van der Maesen, Rhynchosia bracteataBenth. ex Bak., C. acutifolius(F.v. Muell.) van der Maesen, C. lineatus(W. & A.) van der Maesen, and C. albicans(W. & A.) van der Maesen showed resistance to pod fly damage, while those from C. platycarpus(Benth.) van der Maesen, C. cajanifolius(Haines) van der Maesen and R. aureaDC. were susceptible. For the pod wasp, some of the accessions from C. scarabaeoides, C. albicans, Flemingia strictaRoxb., and R. bracteata(Roxb.) Wight showed a resistant reaction, while ICPW 83 belonging to C. scarabaeoidesshowed a susceptible reaction. ICPW 141, ICPW 278, and ICPW 280 (C. scarabaeoides), ICPW 214 (R. bracteata), ICPW 14 (C. albicans), and ICPW 202 (F. stricta) showed resistance to both pod fly and pod wasp damage. There was considerable variation in accessions belonging to different species for their susceptibility to pod fly and pod wasp, which can be exploited to breed for resistance to these pests. There was a negative association between pod wasp and pod borer damage, and therefore, it is important to keep track of the relative susceptibility of pigeonpea genotypes to pod wasp, while breeding for resistance to pod borers.

Short-duration groundnut cultivars were screened under high, medium and low rosette disease pressures and evaluated for rosette disease incidence, presence of groundnut rosette assister virus and other agronomic characteristics. Heritabili- ties of these characteristics and interaction plus variance components across the three disease pressures were calculated. Significant differences among the entries were observed for both agronomical parameters and disease resistance. Broad-based heritabilities for pod and kernel yields under high disease pressure were higher than the values for rosette resistance. It is expected from the results that the genetic improvement for rosette disease resistance will be higher using pod yields as a selection criterion. The interaction components between cultivars and disease pressures were significant, suggesting different responses of the cultivars across the three disease pressures. Yield stability may only be introduced when the cultivars are evaluated under different disease pressures.