Association and path coefficient analysis among yield attributes and berry yield in black pepper (Piper nigrum L.)

Eighty two germplasm accessions of black pepper aggregated from pepper cultivating tracts of Karnataka, Kerala, Goa and Maharashtra were characterized for 17 quantitative traits as per the IPGRI descriptors during 2018-19 at the field gene bank of ICAR-Indian Institute of Spices Research, Experimental Farm, Kozhikode. Wide range and high coefficient of variation (CV) were recorded for dry berry weight, fresh berry weight and number of spikes vine-1 whereas, lower CV was observed for berry size. Fresh berry weight showed significant positive correlation with dry berry weight followed by number of spikes vine-1 whereas, number of immature berries spike-1 and berry size showed significant negative association with setting percentage. High positive direct effect of fresh berry weight on dry berry weight was observed during path analysis. Both fresh rachis weight and number of spike vine-1 had indirect positive effects on dry berry weight through fresh berry weight. Residual effect was meagre suggesting that the 17 quantitative traits explained 99% variability. Traits like number of spikes vine-1 and fresh berry weight are the important traits that need to be augmented during improvement of black pepper for yield

New stable QTLs for berry weight do not colocalize with QTLs for seed traits in cultivated grapevine (Vitis vinifera L.)

International audienceBACKGROUND: In grapevine, as in other fruit crops, fruit size and seed content are key components of yield and quality; however, very few Quantitative Trait Loci (QTLs) for berry weight and seed content (number, weight, and dry matter percentage) have been discovered so far. To identify new stable QTLs for marker-assisted selection and candidate gene identification, we performed simultaneous QTL detection in four mapping populations (seeded or seedless) with various genetic backgrounds. RESULTS: For berry weight, we identified five new QTLs, on linkage groups (LGs) 1, 8, 11, 17 and 18, in addition to the known major QTL on LG 18. The QTL with the largest effect explained up to 31% of total variance and was found in two genetically distant populations on LG 17, where it colocalized with a published putative domestication locus. For seed traits, besides the major QTLs on LG 18 previously reported, we found four new QTLs explaining up to 51% of total variance, on LGs 4, 5, 12 and 14. The previously published QTL for seed number on LG 2 was found related in fact to sex. We found colocalizations between seed and berry weight QTLs only for the major QTL on LG 18 in a seedless background, and on LGs 1 and 13 in a seeded background. Candidate genes belonging to the cell number regulator CNR or cytochrome P450 families were found under the berry weight QTLs on LGs 1, 8, and 17. The involvement of these gene families in fruit weight was first described in tomato using a QTL-cloning approach. Several other interesting candidate genes related to cell wall modifications, water import, auxin and ethylene signalling, transcription control, or organ identity were also found under berry weight QTLs. CONCLUSION: We discovered a total of nine new QTLs for berry weight or seed traits in grapevine, thereby increasing more than twofold the number of reliable QTLs for these traits available for marker assisted selection or candidate gene studies. The lack of colocalization between berry and seed QTLs suggests that these traits may be partly dissociated

Differential response of some seeded grape cultivars of Vitis vinifera to gibberellin application

Several seeded cultivar,s of Vitis vinifera varying in seed content and berry size were tested to see their response to GA application. Oultivars with high seed index number and low seed content like Bhokri, Anab-e-Shahi, Gros Colman (Pusa) and Alamwick did not show any toxic effects due to GA application but responded by producing seedless berries and increasing berry weight with prebloom and postbloom application respectively. Alamwick alone, with high seed index number did not respond to GA by increasing the berry weight but it responded by forming seedless berries. Oultivars like Bharat Early, Black Hamburg and Black Muscat with high seed content per berry and low seed index number did not respond to GA by producing seedless berries and increasing berry weight. This differential response of cultivars to exogenous GA is discussed on the basis of physiological differences in the two groups of cultivars

Genetic variability of berry size in grapevine (Vitis vinifera L.)

Background and Aims: Berry weight in the grapevine, as in the tomato, is variable, ranging from less than 1 g to10 g. In the tomato, berry weight depends on cell number and volume but also on carpel number. The aim of this work was to decipher the range of variation and to propose a role for subtraits possibly underlying berry size variation in a highly diverse collection of cultivated grapevines.Methods and Results: Cell division before and after anthesis and cell expansion after anthesis appeared to be the major determinants of flesh weight variation between cultivars. Carpel number varied between cultivars, with two and three carpels per ovary. This trait, however, and also the seed weight did not clearly contribute to berry size variation, although a positive correlation was found between seed weight and number and berry weight at the intragenotypic level, in agreement with previous results.Conclusions: This work deciphered the main anatomical factors underlying variation in berry size in Vitis vinifera;they involved both common fleshy fruits factors but also specific vine factors.Significance of the Study: Further studies of the variation in berry size of the the grape will be assisted by the anatomical factors identified in this study

Berry Characterisation of cv Shiraz According to Position on the Rachis

In this study, characterisation of the physical and compositional parameters of berries located in differentpositions on the rachis of Shiraz/R99 bunches was done. Berries were divided according to position onthe rachis (apical, median and basal) and berry weight, resulting in four berry weight classes, averaging0.86 g, 1.29 g, 1.74 g and 2.26 g and 0.74, 1.18, 1.59 and 2.09 cm3, respectively. The berries were analysedindividually. The fresh weight of the berries comprised approximately 4% seeds, 20% skin and 76% flesh.Different percentage distributions were found for each class of berry weight and according to position onthe rachis. From the top to the bottom rachis position, an increase in skin proportion value and a decreasein flesh and seed proportion value occurred. Skins decreased and flesh increased in proportion from thesmallest to the largest berry size. The seed maintained a relatively stable proportion, irrespective of berrysize. Larger berries had more flesh compared to skin than smaller berries. A higher level of soluble solidsoccurred in the shoulder to middle bunch area (28.7 °B and 28.6 °B, respectively) than in the bottom area(27.6 °B). It is extremely difficult to obtain uniform berry size and composition under field conditions.Continuous efforts are required to reduce variation and the potential negative impact on wine quality andconsistency of wine style

Production of Direct Seeded Unihot Pepper in Sand Soil

The aim of our study was to investigate the production of direct seeded Unihot pepper. In our measurements the following parameters were examined: yield, average berry weight, capsaicin and pigment content. Open field experiments were carried out at Univer Product Plc. in Szentkirály in 2018

The application of gibberellic acid increases berry size of ‘Emperatriz’ seedless grape

Gibberellic acid (GA3) increases berry size of "Emperatriz" seedless grape, the response depending on the phenological stage of vine at treatment date and on the concentration applied. From berry fruit set to 21 days later, 80 mg/L GA3 increased commercial berry weight by 50%-90%, depending on the year, reaching similar size to that of "Aledo" seeded grape, used as comparison. This effect takes place through: a) a larger berry growth rate; b) an early glucose, fructose and sucrose uptake; c) an increase of absolute glucose and fructose content (mg/berry) of seedless berries up to similar values to those of seeded berries; and d) an increase of absolute berry water content but not of relative content to fresh weight, thus water potential and osmotic potential are not significantly modified by treatments. GA3 does not affect berry pericarp cell number but increases pericarp cell diameter

Character association studies in grape accessions selected from Leh district of Jammu and Kashmir

Characters association and path analysis was studied in fifty genotypically diverse grape (Vitis vinifera L.) accessions for 20 important quantitative characters. The genotypic and phenotypic association of yield was signifi-cantly positive with most of the studied characters except yield efficiency, berry weight and chemical characters. Yield was positively and significantly correlated (r) with bunch length (0.652), bunch breadth (0.584), bunch weight (0.946), number of bunches per vine (0.289), number of berries per bunch (0.672), berry length (0.337), berry breadth (0.363) and number of seeds per berry (0.612). Direct and positive effect was observed between yield and bunch and berry characters. Bunch breadth (1.538), number of bunches per vine (0.708), berry weight (1.112) ex-hibited a good amount of direct effect on yield and its correlation with yield was also positive. Hence it is clear from the present study that for selection of any accession in the crop due emphasis must be given on the yield and the associated characters which have direct and positive effect on the yield