Impact of Alternaria solani (Early blight) on cultivated tomato (Solanum lycopersicum L.) in North-eastern region of India and identification of early blight disease resistant tomato genotypes

Abstract

Abstract:The present investigation was carried out to screen genotypes for resistance to Early blight disease of tomato (Solanum lycopersicum L.) of North Eastern region of India. Field trial was conducted in the Experimental Farm, Department of Horticulture, Assam Agricultural University, Jorhat during the years 2012-13 and 2013-14 consecutively. The disease severity of tomato genotypes was assessed by 0-5 points scale, percent Disease Incidence (PDI). Of the total materials screened, Sel-35 (TLBRH-6 X Konbilahi) and Sel-19 (TLBRH-6 X Konbilahi) were highly resistant, 7 were resistant, 14 were moderately resistant, 16 were susceptible and 6 were highly susceptible under field condition after inoculation during both years. The genotype having high yield and resistant to early blight was 10/TOLCVRES-3. The genotypes resistant to early blight but having low yield and Sel-16) may be utilized in future breeding programme for improving yield through selection for higher fruit weight and fruit diameter. Alternatively, they may be used as parents in hybridization or backcrossing programme in order to transfer the gene for resistance to early blight to already adapted high yield varieties.

Genetic Variability and Character Association Analysis for Quantitative and Qualitative Traits in Tomato (Solanum Lycopersicum L.) Hybrids Under Protected Environment

“…High heritability together with high genetic advance as % of mean was observed in plant height (99.49 %, 61.19%), total soluble solids (98.35%, 55.29%), total number of fruits per plant (98.08%, 72.18%), flowering days (98.11%, 45.29%), days to first fruiting (80.14%,10.00%) and number of cluster per plant (90.77%, 32.49%), number of flower per cluster (89.51%, 34.14%), number of fruits per cluster (87.16%, 36.78%), fruit length (86.60%, 26.63%), fruit diameter (68.31%, 19.02%), number of locule per fruit (92.76%, 38.46%), pericarp thickness of fruit (89.49%, 21.03%), average fruit weight (92.95%, 15.88%), fruit yield per plant (86.01%, 33.45%) indicating strong influence of additive gene action and phenotypic selection is effective for these traits. Analogous observations were found by (Lekshmi and Celine 2017); (Ritonga et al, 2018);(Tasis et al, 2012) and (Meitei et al, 2014).…”

Response of Different Tomato Accessions to Biotic and Abiotic Stresses

“…High heritability coupled with high genetic advance was observed for plant fruits, single fruit weight, fruit yield per plant, fruit clusters, plant and fruit yield indicating the presence of additive gene effects which may be utilized for improvement through phenotypic selection for yield improvement. High heritability with moderate to low genetic advance was observed for days to 50% flowering and fruiting, first and last picking, plant height and fruit diameter (Meitei et al, 2014).…”

Bacillus velezensis YXDHD1-7 Prevents Early Blight Disease by Promoting Growth and Enhancing Defense Enzyme Activities in Tomato Plants

“…The pot experiment was performed in a greenhouse at 28 • C and a relative humidity of 60%. The disease incidence was recorded at thirty days post inoculations and was rated using the previously mentioned scale, with some modifications [29]. Briefly, the plants were evaluated based on their individual disease rating grade in each treatment, where 0 = free from infection; 1 = a few spots on the leaves, covering less than 25% of the total leaves' surface area; 2 = many spots covering 25-50% of the total leaves' surface area; 3 = spots covering 51-75% of the total leaves' surface area; 4 = spots covering more than 76% of the surface area.…”