Cowpea aphid performance and behaviour on two resistant cowpea lines

Abstract

In a series of laboratory and climate chamber tests we compared the growth and behaviour of Aphis craccivora on one susceptible (ICV-1) and two aphid-resistant (ICV-11 and ICV-12) cowpea lines. The aphids' growth rates were much lower on the resistant cowpea lines than on the susceptible one, indicating strong antibiosis. In addition, the aphids invariably settled in higher numbers on the susceptible line than on either of the resistant. Compared to ICV-1, damaged leaves of the resistant line ICV-12 were settled upon to a higher degree than undamaged leaves, and leaf discs from the same line were even less resistant.On resistant lines individual aphids waited a significantly longer time before making their first test probe. Total probing time as well as the time preceding a decision to stay or leave was also longer.These results are discussed in relation to the possible mechanisms involved, and we also consider the effects of previous leaf feeding on the expression of resistance in the field.

Population Dynamics and Clonal Comparisons of Cowpea Aphid (Homoptera: Aphididae) on Resistant and Susceptible Cowpea Cultivars

“…Therefore, results of this work and the other studies indicate that both antibiosis and antixenosis are mechanisms of A. craccivora resistance in ICV-12. This is consistent with findings in similar studies with ICV-12 and other resistant cowpea cultivars (Givovich et al 1988;Firempong 1988;Ofuya 1988a, b). Also, it is obvious from the laboratory study in this work and the aforementioned complementary studies that the factor that is responsible for ICV-12 resistance against the aphid is based in phloem sieve elements in seedling foliage.…”

“…Similar to the trend observed in tests on whole plants, expression of plant resistance on aphid life table parameters on excised seedling leaves ofICV-12 were stronger than that observed for ICY-12. This suggests that injury to plants through excision did not alter the adverse effects of ICY-12 on aphid performance, contrary to observations by Givovich et al (1988).…”

“…Aphid resistance in ICY-12 is governed by a single dominant gene (Pathak 1988). Givovich et al (1988) and Firempong (1988) determined that both antibiosis and antixenosis were important mechanisms of ICY-12 resistance. However, those authors did not elucidate the tissue location of the resistant factors.…”

Interaction between aphid resistant cowpea cultivars, three clones of cowpea aphid, and the effect of two light intensity regimes on this interaction

“…Nymphal survival, development and fecundity were all generally severely affected (Table 1), particularly for clones N4 and N2, indicating a high level of resistance to the cowpea aphid, probably because of antibiosis (Painter, 1951). Givovich et al (1988) observed much lower growth rates for A. craccivora on resistant cowpea lines than susceptible ones and they suggested strong antibiosis as the resistance mechanism. However, Saxena (1985) suggested that failure to survive may be caused not only by antibiosis, but also by a failure to obtain an adequate food supply; this could belong to the feeding non-preference category of resistance.…”

Developmental Characteristics and Feeding Behavior of Green Peach Aphid (Myzus persicae) on Sweet Pepper (Capsicum annuum) Cultivars

“…이러한 저항성 품종을 선발하기 위해서 품종별 대상 곤충의 생명표를 작성하거나 EPG와 같은 전기생리학적 기법을 통해 섭식행동을 측정하여 비교한 연구결과들을 확인할 수 있 는데, 국내에서는 복숭아혹진딧물의 기주식물의 품종별 성충수 명과 산자수를 조사하거나 (Song and Motoyama, 1996;Choi et al, 2001;, 발육기간, 생존율, 산란율을 조사하 여 작성한 생명표로 유전자변형작물과 모본 작물간의 차이를 확 인하기도 하였다 (Kim and Kim, 2004). (Billy et al, 1997;Givovich et al, 1988;Ofuya, 1988). Billy et al(1997), Ruggle and Gutierrez (1995), Guldemond et al(1998) …”