Interaction Effect of Applied Calcium and Magnesium on Alfisols of Karnataka and its Influence on Uptake and Yield Levels of Tomato (Solanum lycopersium L.)

In a field experiment, interaction effects of applied Ca, Mg and K on yield and quality of tomato and soil nutrient levels was studied in Alfisols of Karnataka. The results showed application of Mg enhanced fruit yield up to 100 kg Mg ha-1 and decreased at higher levels of Mg. The application of Ca also enhanced the yield of tomato but their combined application at different levels had negative effect of one on the other. The results indicated that optimum combination of Mg and Ca was 100 and 250 kg ha-1 respectively for obtaining higher yield in tomato. Soil P content enhanced with application of both Ca and Mg. However, applied Ca and Mg showed significant negative effect on both soil and K content. Interaction effect was however, non-significant on soil pH, EC, OC and Soil N content

Evaluation of F1 Hybrids and their Parents for Growth, Yield and Quality in Cherry Tomato (Solanum lycopersicum Var. cerasiforme)

The present study was carried out to estimate the performance of F1 hybrids and their parents for various yield and yield-attributing traits in cherry tomato, at Division of Vegetable Crops, Indian Institute of Horticultural Research (IIHR), Bengaluru, during the year 2010-11. Among the seven parents used, three parents, namely, IIHR-2866 (yielding 3.03kg/plant), IIHR-2864 (2.87kg/plant) and IIHR-2865 (2.73kg/plant) were found to be high-yielding. Among the 21 F1 hybrids evaluated, three hybrids, namely, IIHR-2754 x IIHR-2860 (4.27kg/plant), followed by IIHR- 2754 x IIHR-2865 (3.97kg/plant) and IIHR-2864 x IIHR-2865 (3.40kg/plant) recorded higher yield than the Check varieties, whereas, three hybrids, viz, IIHR-2754 x IIHR-2865 (54.38t/ha), succeeded by IIHR-2863 x IIHR-2866 (46.46t/ha) and IIHR-2858 x IIHR-2866 (44.79t/ha), recorded higher estimated yield per hectare than the Check varieties. Hybrid IIHR-2754 x IIHR-2860 was found promising for most of the traits studied. The best performing parents can be used for breeding further while, the hybrids can be exploited commercially

Combining ability, gene action and heritability analysis for early blight resistance, yield and quality traits in tomato (Solanum lycopersicum L.)

Nine tomato genotypes were crossed in Line ×Tester fashion to develop 18 hybrids, which, along with their parents and checks were evaluated for early blight resistance, fruit yield and quality of tomato (Solanum lyco-persicum) to know extent of combining ability for the same. IIHR1816 was found to be the best general combiner with significant highest GCA (General Combining Ability) in desirable direction for per cent disease index (-15.71), carotenoids (3.46), lycopene (2.43) and yield (13.13); while, for plant height (3.94), average fruit weight (25.93), fruit length (0.54), fruit breadth (0.63) and pericarp thickness (1.71), the line IIHR2848 was best general combiner. The tester IIHR2852 was a best general combiner for traits like days to 50% flowering (-0.83) and fruit firmness (0.51).The crosses viz., IIHR2891 × IIHR2853 (11.61), IIHR2850 × IIHR2852 (11.40) and IIHR2892 × IIHR2890 (11.19) were found to be superior specific combiners for yield. IIHR2892 × IIHR2852 was a superior specific combin-er for fruit quality traits like fruit firmness (0.98), total carotenoids (6.95) and lycopene (4.52).Best specific combiners for early blight resistance were IIHR2850 × IIHR2852 (-9.58), IIHR2891 × IIHR2890 (-9.58) and IIHR2892 × IIH-R2890 (-6.82). The experiment helped in identifying these superior general combiners and specific combiners for early blight resistance, coupled with good yield and quality of the crop, which can be used in further breeding under-takings

Combining Ability for Yield and Yield-Related Traits in Manjarigota Type Brinjal (Solanum melongena L.)

Twenty one F1 crosses of Manjarigota type of brinjal in a line X tester (mating design) involving seven lines and three testers were evaluated for general combining ability (GCA) of the parents and specific combining ability (SCA) of the crosses for various quantitative characters. Combining ability analysis revealed that two lines viz, IIHR-574 (L3) and IIHR-575 (L4), and two testers, IIHR-438-2 (T1) and IIHR-500A (T2) were good general combiner for most of the characters studied and, hence, can be used for further improvement of quantitative traits in Manjarigota type of brinjal. Among the 21 F1 crosses evaluated, two crosses, L4xT2 and L3xT3, were found to be good specific combiners for most of the yield contributing traits, viz, fruit length, fruit diameter, number of fruits per plant, fruit yield per plant and plant height. Therefore, these cross-combinations can be commercially exploited for heterosis breeding to isolate desirable genotypes of manjarigota type brinjal

Screening a set of tomato parental lines and their hybrids for resistance to early blight (Alternaria solani) by detached leaf method

Nine parental lines and 18 hybrids derived by crossing them in Line × Tester fashion were screened against the early blight pathogen Alternaria solani along with a resistant, susceptible and a commercial check in the form of Arka Rakshak, IIHR2202 and Abhinava respectively. Parental lines and the resistant and susceptible checks were screened over two seasons and results obtained were almost similar with the line IIHR1816 exhibiting resistance with the disease severity of 25 % in both the trials, while the line IIHR977 was found to be resistant in the first season with PDI of 25 % and moderately resistant in the second season with the slightest increase in the disease severity up to 25.6 %. None of the hybrids were found to be resistant except, whereas about eight hybrids were found to be moderately resistant. IIHR2892 x IIHR2853 was found to be highly susceptible with severity of 68.75 %, which is on par with the susceptible check IIHR2202 (70.50 %). The results obtained from the detached leaf method of screening should be confirmed by the field or greenhouse screening methods before using them in further breeding programmes

Effect of Applied Magnesium on Yield and Quality of Tomato in Alfisols of Karnataka

Field experiments were conducted for two years on Alfisols to assess the effect of applied magnesium on fruit yield and quality parameters in tomato. Magnesium was applied at four levels ranging from 0 to 100 kg/ha in the form of MgSO4. Applied Mg significantly enhanced fruit yield up to 50kg /ha during the two years of experimentation. Tomato quality parameters viz., total titrable acidity, content of lycopene, total carotenoids and ascorbic acid differed significantly among treatments. Applied Mg significantly improved quality. Highest lycopene content, carotenoids and ascorbic acid in the fruit was recorded in Recommended Dose of Fertilizers (RDF) + MgSO4 @ 50Kg/ha followed by RDF + MgSO4 @ 75 kg/ha. Lowest values for the above parameters were observed in the treatment receiving RDF alone in both the years

Changes in Fruit Quality and Carotenoid Profile in Tomato (Solanum lycopersicon L.) Genotypes under Elevated Temperature

Tomato (Solanum lycopersicon L.) is a rich source of carotenoids, especially lycopene, and is affected severely by high temperatures under tropical conditions. To study the effect of elevated temperature on lycopene content and other quality parameters, five tomato genotypes, viz., RF4A, Abhinava, Arka Saurabh, IIHR 2195 and Arka Vikas, were grown in a temperature gradient tunnel (TGT) facility under 33.4 and 35.4°C temperature conditions. Fruits were analyzed for total carotenoids, total phenols, total flavonoids, total sugars, TSS, acidity, Vitamin C besides carotenoids profile (β-carotene, lycopene, phytoene and luteoxanthin content). Results revealed that all the quality parameters studied were superior at 33.4°C, compared to 35.4°C in all the genotypes. 'IIHR 2195' recorded highest total phenols (479.28mg/100g dw), total flavonoids (70.27mg/100g dw), ferric reducing antioxidant potential (FRAP) (310.53mg/100g dw), diphenyl picryl hydrazyl (DPPH) radical (487.89mg/100g dw), Vitamin C content (292.25mg/ 100g dw) and total sugars (606.88mg/g dw) at 33.4°C and at 35.4°C. 'RF4A' and 'Arka Vikas' were found to have better total carotenoids content and lycopene at higher temperature than other genotypes. 'Arka Vikas' recorded highest total soluble solids (TSS) (8.9°Brix) and acidity (0.80%) at 35.4°C. Higher TSS and acidity were recorded at 35.4°C than at 33.4°C in all the five genotypes. Genotypic variation was observed in the above stated biochemical parameters in response to elevated temperatures

Carotenoid Content in Cherry Tomatoes Correlated to the Color Space Values L*, a*, b*: A Non-destructive Method of Estimation

Cherry tomatoes are rich sources of carotenoids. The carotenoids are known to be precursors of vitamin A and also act as an antioxidant. It is important to visually judge the tomato surface color for higher β carotene content since this is the major provitamin AA carotenoid. Estimation of carotenoids by HPLC (High Performance Liquid Chromatography) and spectrophotometric methods in tomatoes are very expensive and time consuming. Therefore, colorimeters can be used to describe the color and determine the carotenoid content in a relatively easy and inexpensive manner. The objective of this study was to determine, if the carotenoid content within cherry tomatoes measured by conventional method could correlate with colorimetric CIE (Commission International del’Eclairage) L*, a*, b* color space values. Strong correlations were found between color surface value a* and total carotenoids (0.82) and lycopene content (0.87). We also observed positive correlation for the b* color value with β carotene (0.86). The L* value was negatively correlated (-0.78) with an increase in carotenoids. These close associations between color space values L*, a*, b* and carotenoids will help the breeders to quickly screen large germplasm/ breeding lines in their breeding program for improvement in carotenoid content through this time saving, inexpensive and nondestructive method at fully ripe stage

Evaluation of Solanum species and eggplant cultivated varieties for bacterial wilt resistance

Bacterial wilt caused by Ralstonia solanacearum is one of the major diseases in Solanum species including cultivated Eggplant (Solanum melongena L.). Bacterial wilt (BW) disease management in eggplant is difficult due to high survival rate of pathogen in soil and chemical application is not eco-friendly. The best way to avoid bacterial wilt in eggplant is using disease-resistant varieties. However, only a limited number of bacterial wilt resistant varieties are available and, there is a necessity to identify and/or develop new resistant varieties. In the current study, wild Solanum species, and eggplant cultivated varieties were evaluated against Ralstonia solanacearum, and disease incidence was recorded. The cultivated varieties IIHR-108, Pusa Purple Long and Rampur Local were identified as susceptible, whereas, IIHR-7 and CARI-1 were identified as resistant to bacterial wilt. These resistant wild and cultivated varieties can be used as a root-stock in bacterialwilt disease resistant breeding programmes

Molecular Mechanisms Involved in Biosynthesis and Regulation of Carotenoids in Plants

Carotenoids are coloured compounds beneficial to plants and humans. Some of the major health benefits carotenoids provide include Vitamin A precursors and, antioxidants besides being involved in several physiological functions. Even though several carotenoids are synthesised by plants, only a few like beta/ alpha carotenes and cryptoxanthin serve as Vitamin A precursors. The rest are useful as antioxidants. To draw maximum benefits from carotenoids, we need to incorporate these in crop improvement programmes for enhancing available Vitamin A precursor carotenoids. Therefore, it is essential to study biosynthesis of carotenoids, their genetics and their control. In this review, we focus on factors regulating carotenoid biosynthesis, metabolism and storage in plastids. Transcriptional and genetic control of carotenoid production in plants is discussed in the review using several mutants too. Further, environmental regulation of carotenoid biosynthesis is also highlighted. Carotenoid-rich fruits and vegetables have greater economic value owing to their health-promoting effects. Besides,carotenoids have several industrial applications. Therefore, knowledge of regulation mechanism in carotenoid production in plants can help develop crop varieties or technologies, thus generating carotene-rich fruits and vegetables