Statistical Models for Stability Analysis in Watermelon

Fourteen promising F1 hybrids of watermelon namely IIHR-188 X IIHR-118, IIHR 114 X IIHR 118 , IIHR 119 X IIHR- 20-1, Arka Manik X IIHR 46, IIHR 43 X IIHR 46, Arka Manik X IIHR-188, Arka Jyothi, NS-295, Kushboo, Madhubala, Apoorva, CWH-7 and Riya were evaluated in experimental plots of Division of Vegetable Crops, Indian Institute of Horticultural Research, Bangalore during 2002-04. Information about biometrical characters such as fruit length (cm), fruit girth (cm), days to first male flower opening&female flower opening, rind thickness(cm) and TSS (%) along with yield (t ha-1), were used to develop stability models to identify stable hybrid(s) for a wide range for cultivation. Stability models thus developed indicated that two hybrids, viz., Arka Jyothi (with yield potential of 75.91 t ha-1) across the years and NS-295 (64.25 t ha-1) were stable for a wide range for cultivation. Statistical measures of stability, viz., regression coefficient, deviation from regression co-efficient and ecovalence measures, were worked out and utilized for grouping of hybrids into different categories based on their cumulative performance over the years

Heterosis and combining ability for yield and its related traits in ridge gourd [Luffa acutangula (L.)Roxb.]

Line × Tester analysis involving three lines and four testers was carried out in ridge gourd [Luffa acutangula (Roxb.) L.]. Significant variation was noticed in the mean performance of the parents and hybrids for all the characters studied except for vine length and fruit girth. The results from GCA and SCA variance indicated the predominance of non-additive gene action for all the traits except fruit girth. Significant heterosis of 177.78% over standard check, Arka Sumeet for fruit weight per plant was expressed by the cross GARG-1 × CO-1. The best general combiners were GARG-1 and Pusa Nutan among the lines, and Jaipur long and CO-1 among testers. Best specific combining ability effects for fruit length and yield (t/ ha) were recorded by the crosses Pusa Nasdar × Arka Sumeet and GARG-1 × CO-1

Genetic variability, correlation and path analysis in bottle gourd (Lagenaria siceraria (Mol. Standl.) germplasm

The present investigation was conducted to determine the variability, heritability, genetic advance and correlation of fruit yield and ten different yield contributing characters in bottle gourd. Wide range of variation was observed for most of the characters like fruit yield/vine, fruit number/vine, fruit weight, fruit yield/ha and node number for first female flower appearance. Phenotypic coefficient of variation was higher than genotypic coefficient of variation for all the traits studied, indicating environmental influence on expression of these characters. However, high heritability (broad sense) along with high genetic advance was recorded by vinelength, branch number, fruit length, fruit width, fruit yield/vine and yield/ha indicating the presence of additive gene effects, hence selection can be employed for the improvement of these parameters. Fruit yield/ ha was significantly and positively associated with fruit number/vine and fruit yield/vine both at genotypic as well as phenotypic levels. Fruit number had maximum direct effect (0.812) on fruit yield/ha followed by fruit weight (0.407), fruit length (0.339), fruit width (0.310), fruit yield/vine (0.249), days taken for first female flower appearance (0.224) and vine length (0.173). Therefore for the yield improvement in bottle gourd, emphasismay be given for indirect selection through fruit parameters like fruit weight, fruit length, fruit number and fruit yield/vine

Genetic Variability and Heritability for Growth and Yield in Cucumber (Cucumis sativus L.)

Quantification of variability is the most essential pre-breeding tool in any crop improvement programme. The present investigation was carried out to assess variability existing in twenty four diverse cucumber genotypes. Results revealed high phenotypic and genotypic coefficient of variation for yield per plant, fruit flesh thickness, number of fruits per plant, number of nodes per plant, number of branches per plant, average fruit weight, internode length and vine length. High heritability, coupled with high genetic advance as per cent mean, was recorded for all the characters studied except days to first female-flower opening, days to 50% flowering and days to first-fruit harvest, indicating a scope for improvement through selection

Studies on Inheritance of Geneic Male Sterility (GMS) and Hybrid Seed Production in Okra [Abelmoschus esculentus (L.) Moench.]

Inheritance of geneic male sterility in GMS line MS-1 of okra [Abelmoschus esculentus (L.) Moench.] was studied using F1, F2 and test-cross generations of crosses between GMS line MS-1 and normal fertile genotypes, and the varieties Arka Anamika, Parbhani Kranti, Arka Abhay, IIHR-108-1-31, IIHR-109-20-6, IIHR-116-23-6, IIHR- 180-6-3, IIHR-161-10-1 and IIHR-130-2-10. All the F1 were found fertile. Segregation of pollen fertility in F2 and test - cross generations involving ms1 was segregated in the ratio 1 fertile: 1 sterile, respectively. This indicated that GMS trait in the line is controlled by a single recessive gene (ms1ms1). Large-scale F1 hybrid seed production in okra becomes rather slow due to the tedious hand-emasculation, followed by hand-pollination, incurring additional labour and cost of F1 seed production. In comparison to fertile lines, this saves approximately 70% time and manual labour. Use of Geneic Male Sterile (GMS) line MS-1 can make F1 hybrid seed production in okra easy and more economical compared to hand-emasculation

Screening for resistance to downy mildew disease [Pseudoperonospora cubensis (Berk. and Curt.) Rostov.] in Cucumber (Cucumis sativus L.)

Downy mildew, a foliar disease caused by the oomycete Pseudoperonospora cubensis (Berk. and Curt.) Rostov, is one of the most destructive disease of cucumber (Cucumis sativus L.). Moderately resistant cultivars are available, but yield losses are high without the use of fungicides, therefore, higher levels of resistance are required to reduce the use of fungicides. Therefore, in the present study, 12 advance breeding lines along with susceptible check of cucumber were screened against downy mildew disease under natural field condition and artificial inoculation through seedling assay technique. The results confirmed that three lines namely IIHR-177-1-1-S7, IIHR-82-1-S6 and IIHR-81-1-S6 were found to be resistant with <10 per cent disease index (PDI) and significantly outperformed against check var. Swarna Agethi for yield and quality traits. These high yielding resistant lines can be utilized as one of the parents for the development of downy mildew resistant hybrids/ varieties

Genetic Variability, Correlation and Path Analysis in Ridge Gourd [Luffa acutangula (Roxb.) L.]

The present investigation was made to determine variability, heritability, genetic advance and correlation of fruit yield with 10 yield-contributing traits in ridge gourd. A wide variability was observed for days taken to first female flower appearance, fruit length, fruit number/plant, fruit weight and fruit yield/ha. Phenotypic coefficient of variation was higher than genotypic coefficient of variation for all the traits studied, indicating environmental influence on the expression of these traits. However, high heritability (broad-sense), along with high genetic advance, was recorded in node number at which first female-flower appeared, number of branches, fruit length, number of fruits/plant and fruit weight, indicating presence of additive gene effects. Fruit yield/ha was significantly and positively associated with peduncle length, fruit length, number of fruits/plant (at the phenotypic level), fruit weight and fruit yield/plant. Fruit weight had the highest direct effect (0.847) on fruit yield/ha, followed by fruit yield/plant (0.793), fruit number (0.344), peduncle length (0.237) and number of branches (0.216). Therefore, for yield improvement in ridge gourd, emphasis may be laid on indirect selection using fruit parameters like fruit weight, number of fruits/plant and fruit yield/plant. &nbsp

Development of Novel Character in Okra [Abelmoschus esculentus (L.) Moench]

Transgressive segregation in the population of IIHR-31-1-2 x Arka Anamika BC3 F1-F6 generations led to the development of, various novel characters such as, ridgeless fruits (round fruit) and enhanced nodal productivity bearing short internodal length in okra selection-1, which was found to be promising for cultivation with high yield and good fruit quality. It can be grown both during Kharif and summer seasons. Okra selection-1 was also found to exhibit smooth fruits, high yield potential with sturdy plant habit and field tolerance to fusarium wilt and YVMV. Due to rapid rate of increase of processing in okra by freezing and canning, Okra selection I may be an ideal fruit type for freezing because of its short, smooth, dark green and round or multifaceted fruits with low mucilage content

Genetic analysis and identification of SSR marker linked topowdery mildew resistance in bitter gourd (Momordica charantia L.)

The inheritance of powdery mildew resistance in bitter gourd resistant line IIHR-144-1 was studied in cross with two susceptible lines Arka Harit and IIHR Sel-5-8. The segregation ratios in F2 and backcross progenies indicated that resistance is governed by dominant-recessive epistasis or dominant inhibitory epistasis, indicating the involvement of more than one pairs of genes, one dominant and one recessive for resistance along with other background minor genes in the resistant line IIHR-144-1. Bulk segregant analysis of F2 population of cross between IIHR-144-1 and Arka Harit using SSR markers identified McSSR 57 produced a polymorphic DNA fragment that co-segregated with disease reaction. Considering the cross compatibility between Momordica charantia L. and M. charantia var. muricata (IIHR-144-1) the resistance trait can be transferred to cultivated species through hybridization and selection

All‐Rounder Low‐Cost Dopant‐Free D‐A‐D Hole‐Transporting Materials for Efficient Indoor and Outdoor Performance of Perovskite Solar Cells

A novel biphenyl fumaronitrile as an acceptor and triphenylamine as donor conjugated building blocks are used for the first time to successfully synthesize donor–acceptor–donor molecule (D-A-D) 2,3-bis(4′-(bis(4-methoxyphenyl)amino)-[1,1′-biphenyl]-4-yl)fumaronitrile (TPA-BPFN-TPA). The new TPA-BPFN-TPA with low-lying HOMO is used as a dopant-free hole-transporting material (HTM) in mesoporous perovskite solar cells. The performance of the solar cells using this new HTM is compared with the traditional 2,2′,7,7′-tetrakis(N,N′-di-p-methoxyphenylamino)- 9,9′-spirobifluorene (Spiro-OMeTAD) HTM based devices for outdoor and indoor performance evaluation. Under 1 sun illumination, dopant-free TPA-BPFN-TPA HTM based devices exhibit a power conversion efficiency (PCE) of 18.4%, which is the record efficiency to date among D-A-D molecular design based dopant-free HTMs. Moreover, the stability of unencapsulated TPA-BPFN-TPA-based devices shows improvement over Spiro-OMeTAD-based devices in harsh relative humidity condition of 70%. Another exciting feature of the newly developed HTM is that the TPA-BPFN-TPA-based devices exhibit improved PCE of 30% and 20.1% at 1000 lux and 200 lux illuminations, respectively. This new finding provides a solution to fabricate low indoor (low light) and outdoor (1 sun) perovskite solar cell devices with high efficiency for cutting-edge energy harvesting technology.</p