Effect of Host Plant Resistance to Tomato yellow leaf curl virus (TYLCV) on Virus Acquisition and Transmission by Its Whitefly Vector

Abstract

The effect that Tomato yellow leaf curl virus (TYLCV)-infected resistant tomato plants may have on virus epidemiology was studied. Four tomato genotypes that exhibit different levels of viral resistance, ranging from fully susceptible to highly resistant, served as TYLCV-infected source plants. Viral acquisition and transmission rates by white-flies following feeding on the different source plants were evaluated. TYLCV transmission rate by whiteflies that had fed on infected source plants 21 days postinoculation (DPI), shortly after the appearance of TYLCV symptoms, was negatively correlated with the level of resistance displayed by the source plant. Therefore, the higher the resistance, the lower the transmission rate. In addition, TYLCV DNA accumulation was shown to be lower in the resistant source plants compared with the susceptible plants. Whitefly survival rate, following feeding on source plants 21 DPI, was similar for all the cultivars tested. Significant differences in whitefly survival were found, however, following feeding on the infected source plants at 35 DPI; here, whitefly survival rate increased with higher levels of resistance displayed by the source plant. At 35 DPI, the susceptible plants had developed severe TYLCV disease symptoms, and transmission rates from these plants were the lowest, presumably due to the poor condition of these plants. Transmission rates from source plants displaying a medium level of resistance level were highest, with rates declining following feeding on source plants displaying higher levels of TYLCV resistance. TYLCV DNA accumulation in whiteflies following feeding on infected source plants at both 21 and 35 DPI was directly correlated with viral DNA accumulation in source plants. Results show that, in essence, the higher the resistance expressed, the less suitable the plant was as a viral source. Consequently, following acquisition from a highly resistant plant, TYLCV transmission by whiteflies will be less efficient.

Introduction and Molecular Characterization of Tomato yellow leaf curl virus in Okinawa, Japan

“…In addition, a few improved early maturing hybrid varieties and TYLCV-resistant varieties were being made available with the host-free period strategy in the DO 7 . Over the last 20 years, many breeding programs have been carried out developing TYLCV-resistant cultivars in the world 10,11,16 . Recently developed TYLCV-resistant (or tolerant) cultivars could be commercially available in Japan.…”

Detection and Sequence Diversity of Begomovirus Associated with Yellow Leaf Curl Disease of Pepper (Capsicum annuum) in West Sumatra, Indonesia

“…The sample plants were determined according to systematic random sampling. However, desease severity was determined by using formula 1, with a modified scale of category according to Lapidot et al (2001). Symptom development was evaluated according to the following scale: 0, no visible symptoms; 1, very slight yellowing of leaflet margin on apical leaf; 2, some yellowing and minor curling of leafled ends; 3, a wide range of leaf yellowing, curling and cupping, with some reduction in size, yet plants continue to develop; and 4, very severe plant stunting and yellowing, pronounced leaf cupping and curling, plant growth stopped.…”

Keparahan Penyakit Daun Keriting Kuning dan Pertumbuhan Populasi Kutukebul pada Beberapa Genotipe Cabai

“…Kepadatan populasi kutukebul pada suatu pertanaman bergantung pada kemampuan peletakan telur imago dan aktivitas makan. Peletakan telur dan aktivitas makan dipengaruhi oleh karakteristik dan morfologi daun seperti bentuk daun, warna daun, trikoma pada daun, dan senyawasenyawa kimia yang dihasilkan dari proses metabolisme sekunder (Lapidot et al 2001;Ganefianti et al 2008;Faizah et al 2012). Pertumbuhan populasi kutukebul yang cepat pada suatu varietas cabai dapat menjadi sumber penyebaran virus yang potensial.…”