Percentage Of Fruit Set Research Articles

RELATIONSHIP BETWEEN FLORAL MORPHOLOGY, FRUIT SETTING BEHAVIOR AND FINAL YIELD IN SOME EGGPLANT (Solanum melongena) GENOTYPES FROM IRAN

Heterostyly in eggplant flowers is a common trait that may affect the fruit production. The objective of this study was to evaluate the impact of heterostyly on fruit setting and yield of 13 eggplant genotypes from Iran. Flowers capable of setting fruit, including long- (LGs) and medium-styled flowers (MEs), accounted for the largest number of flowers (43.60-75.62%), while total short-styled flowers (SRTs) constituted a smaller percentage (20.47-45.51%) in different genotypes. However, SRTs represented a considerable proportion of the total number of eggplant flowers. Different eggplant genotypes produced 42.59-77.25% fruits from LGs+MEs, and only 0.0-3.77% from SRTs. In general, although the percentage of fruit setting of LGs and MEs was much greater compared to values of SRTs, there was no significant correlation between final yield and style length. Therefore, in order to increase eggplant yield, protecting fruits formed from LGs and MEs might be more effective than increasing the proportion of LGs and MEs to SRTs.

Intra-Specific Crosses in Tomato (SolanumLycopersicon L.) for Improvement of Fruit Quality: A Strategy for Enhanced Food Security

Breeding programme on improvement of tomato fruits and seed production were conducted in the cropping seasons of 2017 and 2018 on three genotypes of tomatoes NG/AA/SEP/09/042, Akungba 1 and Akungba 2. Randomized complete block design replicated three times was adopted on seedlings raised in the nursery for 2 – 3 weeks and transplanted at a spacing of 30 cm x 60 cm within and between rows. Morphological and yield traits were measured and all cultural practices such as weeding, thinning, pest and disease control measures were carried out in order to ensure a disease-free condition and clean environment. At flowering stage, crosses were carried out on the genotypes and successful fruit set were monitored till maturity, ripen fruits were plucked and seeds extracted from the berry, air-dried under ambient temperature of 27 0 C to 30 0 C and relative humidity of 60 – 70% for about 5 – 6 days. Among crosses, the highest percentage fruit set of 77.04% was obtained in BxC followed by CxB with 75.65%; the lowest value of 66.67% was recorded in AxC. Aborted crosses were highest in CxA (31.58%), followed by AxB (29.31%) while the lowest (24.04%) was obtained in BxC. Except for the number of locules, quantitative traits were significantly different from one another; PCV was greater than GCV for all traits and highly significant positive correlation existed between number of fruits per plant and number of clusters per plant. Marketable fruit size and weight with beefsteak shape were obtained in BxC and AxC crosses.

Identification of new sources of heat tolerance in cultivated and wild tomatoes

Heat stress adversely affects tomato production worldwide. Breeding thermotolerant varieties is critical to adapt to increased heat stress but tomato has a narrow genetic base for heat tolerance. Identification of new sources of heat-tolerant germplasm is important to understand physiological and molecular mechanisms of adaptation to heat stress and to broaden the genetic base of heat tolerance in tomato. Here, we screened a germplasm collection comprised of 42 tomato entries using 19 quantitative (physiological, reproductive, and morphological) and five qualitative traits. The plants were grown under long term mild heat stress with temperatures and relative humidities ranging from 23.3 to 37 °C, and 47 to 100%, respectively. The analysis of variance revealed significant differences among the entries for all the quantitative traits. Biologically significant associations were recorded for many traits. Proportion of viable pollen was not associated with fruit set percentage. The clustering analysis groups the germplasm into five clusters with a clear distinction between Solanum lycopersicum and Solanum pimpinellifolium entries. We also observed differences between the entries based on their origins. Known thermo-tolerant entries were found in Clusters 3 (eg.: LA2662, LA3317, LA3120) and 4 (e.g.: CL5915-93D4-1-0, CLN1621L, LA2661). Lines BJ01, BJ02 from Republic of Benin, and WAC1 and ATS020 from Ghana in Cluster 3 are potential new sources of thermo-tolerance in tomato. Generation of hybrids from parents belonging to the clusters 1 to 4 identified in this study would improve heterosis for heat tolerance traits in tomato. Useful traits like high pollen viability and high inflorescence numbers per plant could be introgressed from S. pimpinellifolium entries into the cultivated tomato. Our study provides important information to improve heat tolerance in tomato.

Developing partial interspecific hybrids of Momordica charantia × Momordica balsamina and their advance generations

Interspecific hybridization and introgression breeding are the major approaches employed to address climate change and food security challenges globally. The present study was conducted to trace the nature of crossing barriers and to introgress novel genes from Momordica balsamina to cultivated bitter gourd Momordica charantia. The hybridization success rate was very low between these two species with a higher rate of seedling mortality. A total of 116 accessions of Momordica charantia (female parent) were used for artificial cross-pollination with Momordica balsamina (IC-467683). Among these, only six female parents belonging to Momordica charantia (DBGS-2, NEH-4, PDMGY-201, Pusa Aushadhi, DBGS-3, and NEH-3) exhibited variable percent fruit set when crossed with Momordica balsamina. Among these interspecific crosses, only one cross combination (Pusa Aushadhi × Momordica balsamina) produced the higher percentage of normal seeds and only one seed was germinated followed by development into a full plant. The pollen-pistil interaction study confirmed the existence of post dynamic barriers in all these unsuccessful crosses. A single plant progeny of M. charantia × M. balsamina was derived and its advanced generations were studied at morphological, cytological, and molecular levels. The plant phenotype predominately resembled the female parent with variation in a few traits. The cytological analysis depicted the normal meiosis and the genomic 2C DNA content of the interspecific hybrid was higher than the female parent. The microsatellite (SSRs) markers analysis showed that amplified fragments of interspecific hybrids exhibited highly conserved similarity with fragments of female parents with a very low frequency of male fragments. The F2 and backcross generations were produced from the single partial interspecific hybrid (Pusa Aushadhi × M. balsamina). Twenty advanced generation F2 plants showed variation with majority traits resembles the female parent. The microsatellite analysis revealed that the progenies of backcross generation amplified the fragments with high similarity to both female (Pusa Aushadhi; M. charantia) and the male parent (M. balsamina). These results confirmed the partial introgression of chromosome segments of M. balsamina. But further generations could not be recovered and advanced generation was died because of chlorosis. It was the first attempt to develop an interspecific partial hybrid and its backcross population which would provide preliminary information on the crossability relationship between these two species for transferring novel gene/s or traits from M. balsamina to M. charantia.

Screening of Tomato Genotypes under High Temperature in North Sinai

The present study was conducted at the Experimental Farm, Fac., Environ. Agric., Sci., Arish Univ., during successive summer seasons of 2018 and 2019, to screening twenty one genotypes of tomato as well as Galaxy 040 F1 as check to high temperature under North Sinai conditions. The analyses of variance for all studied traits revealed that mean squared of genotypes were highly significant under high average day/night-time temperature (34.6 oC and 23.9 oC, respectively) of two seasons. The studied lines CLN 1621F, Rio Grande and CLN2514A were the best for floral traits. However, the superior genotypes for fruit set percentage were CLN2026D and Rio Grande. Results of screening revealed that CLN2514A was the best for no. fruits/plant, CLN2413D and CLN1466EA for average fruit weight and CLN1621F for fruit yield /plant (2.84 kg). The highest content of proline recorded by CLN1621F and CLN3125L. Tomato genotypes ranked based on cumulative score to tolerant, moderately tolerant, moderately sensitive and sensitive groups. The clustering pattern of tomato entries grouped into five clusters. The clusters 1, 3 and 4 consisted of three genotypes, whereas the clusters 2 and 5 involved nine and four ones, respectively. Principal component analysis revealed that first two components participating 81.3% of total variability. The highest contribution towards total variability in PC1 and PC2 reflected by no. pollen grains/anther, pollen viability%, branches/plant, fruit set%, fruit yield/plant, average fruit weight, no. seeds/fruit and proline content traits, suggesting that these traits might be taken in concern for successful selection of tomato genotypes under high temperature.

Sweet Cherry (<i>Prunus avium</i> L.) Fruit Drop Reduction by Plant Growth Regulators (Naphthalene Acetic Acid NAA and Gibberellic Acid GA<sub>3</sub>)

This study was conducted during 2019/2020 on sweet cherry trees (Prunus Avium L.) (Bing and Hardy Giant) cultivar planted at Sergaya-Al_Zabadani area of Rural Damascus, to reduce fruit drop of sweet cherry. The experiment included 4 foliar applications: T1: control, T2: GA3 (100 ppm), T3: NAA (20 ppm), T4: (100 ppm GA3 + 20 ppm NAA). Fruit set and fruit drop percentage, fruiting factor, and yield were recorded. The results showed that treatment with (100 ppm GA3 + 20 ppm NAA) recorded higher fruit set percentage (73.81% and 75.62%), and fruiting factor (48.38% and 50.04%) respectively; In addition to fruit yield (40.19 and 41.21 kg/tree) for both cultivars, compared to the control (9.13, 6.60 kg/tree). Therefore, it can be concluded that GA3 + NAA treatment reduced Sweet cherry fruit drop better than other treatments, where fruit drop percentage didn’t exceed (63.11% and 62.01%) in both cultivars (Bing and Hardy Giant) respectively, compared to the control (80.92% and 80.64%).

Effect of different plant growth regulators on growth, yield and quality parameters of cucumber (Cucumis sativus L.) cv. Kalyanpur green

An investigation was carried out at the Vegetable Research farm, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur during Kharif season of 2018. The soil of the experimental field was sandy-loam with uniform topography. The experiment was laid out in a randomized block design replicated thrice with nine treatments i.e. T1 - foliar application of GA3 (100ppm) at 15 days after sowing, T2 - foliar application of GA3 (150ppm) at 30days after sowing, T3 - foliar application of GA3 (200ppm) at 45days after sowing, T4 - foliar application of NAA (100ppm) at 15days after sowing, T5 - foliar application of NAA (150ppm) at 30days after sowing, T6 - foliar application of NAA (200ppm) at 45 days after sowing, T7 - foliar application of Ethrel (200ppm) at 2-4 leaf stage, T8 - foliar application of Ethrel (300ppm) at pre flowering and T9 - Control (Water Spray). The result shows that an application of Ethrel 200ppm was found most effective in reducing the number of male flowers (90.75) in comparison to female flowers (52.08). GA3 200ppm reduce the number of days required for appearance of first flower (36.58 days) of cucumber plant, increased the production of female flowers (50.25), lowered the male and female sex ratio (1.70: 1), increased number of fruits per plant (11.67), increased yield per plant (3.89 kg) and per hectare (180.69 q). The next best treatment was GA3 100 ppm which increased the yield of fruits per plant (3.42 kg) and yield per hectare. From the results of this investigation, it could be inferred that Ethrel 200 ppm treatment was found most effective in improving femaleness with increased fruit yield of cucumber cv. Kalyanpur Green'. Results revealed that the application of plant growth regulators significantly increased growth. GA3 (100ppm) play an important role in increasing yield characters followed by NAA (100 ppm) and male and female flower ratio can be lowered by the application Ethrel (300 ppm). The fruit set and fruit retention percentage was improved through the application GA3 (150ppm) followed by GA3 (200ppm).

Phenotypic assessment of pear varieties in mutual pollination

The self-fertility and cross-fertility of pear varieties have been studied in the conditions of the of the Krasnodar region. It was established that most of the not varieties are self-fertile. The varieties are distinguished: Ladozhskaya, Malyshka and Talgar beauty, with partial self-fertility, in which a low percentage of fruit set and its fluctuation over the years are noted. Based on the pollination performed and the analysis carried out, good and acceptable pollinators for promising pear varieties were selected. It has been established that in order to form full-fledged seeds in the fruit of the pear, a full cross-pollination with good pollinators is necessary. The possibilities of individual varieties (a high percentage of fruit tying) with mutual pollination are presented. The analysis of the negative influence of technogenic factors during flowering on the inter-pollination of varieties has been carried out. Cross-pollinated varieties have a narrow selective ability to pollinate varieties, which varies over the years and depends on the growing conditions. Proved the need, when laying gardens correctly choose varieties-pollinators in order to increase the yield of varieties. According to the research results, a self-fertile variety Iyulskaya early was identified. The best pollinators were selected for promising pear varieties for the conditions of the Kuban.

Induction of flowering and increasing fruit yield and quality in pomegranate (Punica granatum L.) cv. ‘Bhagwa’ by application of certain chemicals

The field trail was conducted at ICAR- IIHR, Bengaluru to assess the effect of different chemicals (Nitrobenzene @ 1.0 ml, 1.5 ml and 2.0 ml/litre, Cycocel @ 500 ppm, 1000 ppm and 1500 ppm, Uracil @ 25 ppm and 50 ppm, Cycocel @ 1000 ppm + Uracil @ 25 ppm and Cycocel @ 1500 ppm + Uracil @ 50 ppm) on flower induction, fruiting and yield parameters in tissue cultured plant propagules of pomegranate (Punica granatum L.) cv. ‘Bhagwa’ during 2016–17 at ICAR-IIHR, Bengaluru. The foliar application of Cycocel @ 1500 ppm gave a significantly increased number of hermaphrodite flowers (287.84) and intermediate flowers (254.14) per plant, thereby increasing the percentage of fruit setting (86.10%) and number of fruits (156.66) per plant. Thus fruit yield (54.53 kg/plant and 21.81 tonnes/ha), fruit weight (348.32 g), fruit length (8.53 cm) and fruit volume (333.93 ml) increased significantly. Consequently, foliar application of Cycocel @ 1500 ppm led to a significant reduction in number of male flowers (219.70) produced per plant. However, fruit width was non-significant among treatments.

Ameliorating thermo-tolerance in bell pepper (Capsicum annuum L. var. grossum) with plant growth regulators

Extreme temperatures have always been a serious threat tobell pepper production owing to its heat sensitivity. Thepresent investigation was planned to assess the effect offoliar spray of growth regulators on morpho-physiologicaland yield parameters in bell pepper cv. Royal Wonder.Spraying bell pepper with Salicylic Acid (SA) and 24-Epibrassinolide (EBR) solutions significantly improved theirtolerance to subsequent high temperatures. Exogenousapplication of three different concentrations of growthregulators i.e SA (0.10 mM, 0.20 mM and 0.50 mM) and EBR(0.05 μM, 0.10 μM and 0.20 μM) were applied at followingstages; 30 days after transplantation (DAT), 60 DAT and 90DAT. These treatments helped in mitigating the heat stressby improving growth parameters (plant height, plant spreadand leaf area), photosynthetic efficiency, membranethermostability, pollen viability and fruit set percent even athigh temperature shows that application of PGRs definitelyplays a role in initiating various mechanisms involved inovercoming high temperature limitations. However, foliarapplication of 0.20 mM SA (30 DAT) followed by 0.10 μMEBR (60 DAT) significantly enhanced the growth and yieldparameters as compared to untreated control.

Effect of different mode of pollination on fruit and seed characteristics of cucumber (Cucumis sativus L.)

Effect of different mode of pollination viz., open pollinationand self pollination on fruit and seed setting as well as theircharacteristics in monoecious (K-75 and UHF-CUC-101) andgynoecious (GYNO-1 and GYNO-2) varieties was studied atthe Experimental Research Farm, Department of VegetableScience, Dr. YS Parmar University of Horticulture andForestry, Nauni, Solan (HP) during Kharif, 2016. Openpollination had better effect on all the parameters (Meanfruit set, mean fruit weight, number of seeds per fruit andthousand seed weight) studied compared to self pollinationmethod. Maximum fruit weight of 278.02g was recorded inopen pollination system than in selfing (263.54g) and it wasrecorded maximum in cultivar UHF-CUC-101 (289.28g) andminimum in GYNO-2 (259.89g). Similarly, number of seedsper fruit was more in open pollination system (190.05 seeds/fruit) than in selfing (160.72 seeds/fruit) and among cultivars,it was found maximum in K-75 (256.30) and minimum inGYNO-1 (99.81). Likewise, thousand seed weight wasrecorded higher in open pollination system (20.12g) than inselfing (18.32g) and amid cultivars maximum in K-75 (22.65g)whereas minimum in GYNO-2 (18.26g). Interactions (Varieties× Conditions) had a significant effect on percent fruit set aswell as number of seeds per fruit and non-significant effecton mean fruit weight and thousand seed weight.

Effect of Spraying Zinc, Copper And Iron on Leaf Nutrient, Fruit Set And Some Fruit Quality of Pistachio Trees (pistacia Vera L.) Cv. Halebi

This study was conducted at a private orchard in the Ekmale village of Duhok Governorate, Kurdistan Region, Iraq during growing season (2020) to evaluate the effect of foliar sprays of three concentrations of zinc (0, 750, and 1500 mg.L−1 ), three concentrations of copper (0, 100, and 200 mg.L−1 ) and three concentrations of iron (0, 150, and 300 mg.L−1 ) on leaf nutrient, fruit set, as well as yield and quality of 18- years old " Halebi " pistachio trees. The nutrition solutions were sprayed on trees at two times (bud swell stage and green tip stage). Based on the obtained results, fruit set percentage, yield, and leaf nutrient were significantly affected by foliar application of a zinc, copper and iron each alone. In combination, the triple interactions among 1500mg.L−1 zinc plus 200mg.L−1 copper and 300mg.L−1 iron was the most affected one which exceed significantly on the control treatment, Moreover, nutrient treatment had a significant effect on the percentage of blankness. In general, these results show that Zn, Cu and Fe fertilizers is necessary for obtaining better yield and fruit quality in " Halebi " pistachio trees.

Productivity of rice as influenced by soil and foliar application of silicon

A field experiment was conducted at Regional Horticultural Research and Extension Centre, GKVK campus, Bengaluru-65, Karnataka during 2019-20 to study the effect of foliar application of zinc and boron from different sources on growth, yield and quality of custard apple (Annona squamosa L.) cv. Arka Sahan. The experiment was laid out in Randomized Complete Block Design with twelve treatments replicated thrice. The treatments consisted of foliar application of 0.5% Zinc sulphate, 0.5% Zinc chloride, 0.5% Zinc oxide, 0.3% Boric acid and 0.3% Borax either alone or in combination, along with water spray as control. Each treatment was imposed thrice to the existing custard apple trees, one at the time of flowering, second at fruit set stage and third at pre-harvest stage. The results revealed that foliar application of 0.5% Zinc sulphate plus 0.3% borax significantly enhanced the growth attributes of custard apple in terms of shoot length (50.60 cm), number of leaves per branch (130.72) and leaf area (130.35 cm2) along with improved yield parameters like number of flowers per tree (564.17), percentage of fruit set (93.33), number of fruits per tree (22.83) and fruit yield per tree (11.09 kg). The same treatment combination yielded the fruits having superior physical quality in terms of highest fruit diameter (9.65 cm), fruit volume (174.59 mL), fruit weight (485.98 g) and pulp weight (353.64 g). The quality parameters of fruit such as reducing sugars (22.03%), total sugars (23.85%), TSS (32.25 0Brix) and ascorbic acid (38.61%) contents of fruit significantly improved along with minimum physiological weight loss during keeping time of 1st day (1.00 %), 3rd day (3.42 %), 5th day (6.27 %) and 7th day (11.01 %) after ripening were recorded with the same treatment combination. Among different treatments, the combined foliar application of 0.5% Zinc sulphate and 0.3% Borax showed best results with regard to growth, yield and quality of custard apple cv. Arka Sahan.

Phenotypic characterization and seed-micromorphology diversity of the threatened terrestrial orchids: implications for conservation

In the current study, phenotypic and seed-micromorphology variability of 106 accessions from Dactlorhiza umbrosa (Kar. & Kir.) Nevski, Himantoglossum affine (Boiss.) Schltr., Orchis mascula (L.) L., Orchis simia Lam., Anacamptis coriophora (L.) R.M.Bateman, Pridgeon & M.W.Chase, Ophrys schulzei Bornm. & Fleischm., Ophrys straussii Fleischm. & Bornm., and Orchis collina Sol. ex Russ. species was evaluated. Most of the evaluated traits represented coefficient variations (CV) <30% mainly for economically valuable traits including inflorescence length, flower number, flowering duration, tuber fresh weight, and tuber dry weight. The highest mean value for tuber width (5.61 ± 1.43 cm), tuber length (7.36 ± 1.27 cm), tuber fresh weight (23.38 ± 4.84 g), and tuber dry weight (2.80 ± 0.40 g) was recorded in Ha.JA population belonged to H. affine. The thickest (260.2 ± 1.50 µm) and the thinnest seeds (150.12 ± 9.29 µm) belonged to Os.P population belonged to O. simia and Du.M population belonged to D. umbrosa, respectively. There were highly significant positive or negative correlations between flower, inflorescence, and tuber characteristics. In this regard, the fruit set percentage was positively correlated with flower number (r = 0.36) and flowering date (r = 0.57). Tuber fresh weight was positively correlated with leaf number (r = 0.66), root length (r = 0.77), and root number (r = 0.63). Furthermore, the principal components with eigenvalue more than 0.45 were defined as being significant where eight components explained more than 93.33% of the total variance. The Ward dendrogram based on the Euclidean distance distinguished six distinct groups where accessions within O. collina, H. affine, O. coriophora, and D. umbrosa were placed in I, II, III, and V clusters, respectively. On the other hand, the accessions within O. schulzei and O. straussii formed cluster IV, while the accessions within O. simia and O. mascula were grouped into cluster VI, respectively. Overall, morphological traits at whole plant scale combined with seed-micromorphology characters not only could discriminate and clarify the relationships among the species and their populations collected from geographically different locations but also they could identify the diversity among the accessions within each population and species.

Performance, Manifestation of Heterosis and Combining Ability for Growth, Productivity and Fruit Quality of Indeterminate Tomato

Six parental lines of indeterminate tomato were used in half diallel model to study performance, degree of heterosis and combining ability.This study was conducted at the Experimental Farm, Faculty of Environmental Agriculture Sciences, Arish University during two successive seasons of 2018/2019 and 2019/2020. Results revealed that the parental lines IRS-43-2, VR-6 and VL-5-4 exhibited the best values for most studied characters,however the cross combinations IRS-43-2 x VR-6, IR-44-2 x VR-6 and VR-6 x VL-5-4 were the best among the crosses.Hybrid vigour was observed in many traits, the significant positive heterosis over the check hybrid was detected in all characters and the highest values were reflected by the crosses VR-6 x VL-5-4 for growth traits and IRS-43-2 x VR-6 for early yield, total yield and Vit. C content. Variances of combining ability and genetic components revealed that additive gene action played the main role in the inheritance of fruit set percentage, total yield plant-1, average fruit weight, fruit shape and Vit. C. Based on GCA effects, the good combiner was Vl-5-4, for growth traits; IRS-43-2 and VR-6 for early yield, total yield, number of locules, and Vit. C. The highly significant positive values of SCA effects observed in crosses VR-6 x VL-5-4 for growth traits and Vit. C; IRS-43-2 x VL-5-4 for early yield; and IR-44-1 x VL-7-4 for total yield and average fruit weight. Three promising crosses (IRS-43-2 x VR-6; IR-44-2 x VR-6; VR-6 x VL-5-4) could be used commercially as local hybrids after testing in multi locations and seasons.

General and specific combining ability in the selection of polliniser cultivars of hybrid pear trees (Pyrus communis x P. pyrifolia)

The major limiting factor in the production of pears in the tropics are the reduced number of pears cultivars adapted and the lack of knowledge of potential pollinisers among the existing cultivars. The pear tree has gametophytic incompatibility requiring a polliniser cultivar. For commercial pear tree growing, in addition to flowering synchrony and gametophytic compatibility, the metaxenia effect, which influences fruit quality, should also be considered when choosing the polliniser cultivar. This study was conducted to estimate the general combining ability (GCA) and specific combining ability (SCA) in diallel crosses to assist in the selection of pollinisers for hybrid pear tree cultivars (Pyrus communis x Pyrus pyrifolia) adapted to the low chill areas. Self-pollinations and cross-pollinations among four pear cultivars (Cascatense, Centenária, D'água, and Primorosa) were carried out in two seasons. The variables fruit set percentage, viable seed percentage, fruit mass, fruit length, fruit diameter, °Brix, and pH were evaluated. Afterward, a diallel analysis was performed, following the Griffing method 1, model 1, to estimate the GCA, SCA, and RE from the parents, F1 hybrids, and reciprocal F1 hybrids obtained in the crosses. The results revealed that Centenária showed a positive additive effect for the variables studied. The cross Primorosa x Centenária showed a high positive effect for all the evaluated traits. These results suggest the existence of a polliniser effect of the hybrid pears cultivars for the characteristics studied. This study presents information of significant value for growers interested in planting pears trees in the tropics and those involved in pears tree breeding.

Studies of three apple pollinizer cultivars on m9 clonal rootstock under high-density plantation in cold dry temperate region of Kinnaur, Himachal Pradesh

A field experiment was carried out at the Vegetable Research Station, Kalpa, to study the performance of three pollinizer cultivars grafted on M9 clonal rootstock under high-density plantations in the cold temperate region of Kinnaur, Himachal Pradesh, situated at an altitude of 27,000 meters. The high-density plantation of apples in Kinnaur district is still in the inception stage and it is important to aware the farmers of the area about pollinizer cultivars improve the production of temperate fruits. Sufficient and judicious incorporation of pollinizer cultivars is indeed an important aspect in the enhancement of productivity, keeping in mind that this trial was carried out to benefit the farming community in the coming years. The experiment evaluates three apple cultivars ‘Gale Gala/M9’, ‘Redlum Gala/M9’, and ‘Auvil Early Fuji/M9’, planted in the year 2016 as a feathered plant at a spacing of 2.5X1.0 meters in Randomized Block Design (RBD). Most of the growth and fruiting characteristics were found to be non-significant and significant results were obtained only in the Number of fruits, Fruit Size, Length and fruit weight. However, Maximum, shoot extension growth (13.86 cm), plant height (219.50 cm), Total Number of flowers Number (1211 / tree), Number of fruit set /tree (64.25), Number of fruits/tree (30.17), Yield (3.79 kg/tree) and Productivity (15.14 MT/Ha) were recorded with Redlum Gala on M9, whereas, trunk diameter (30.50 mm), plant spread N-S (120.83 cm), fruit diameter (81.21 mm), percent fruit set (23.06 ) and Fruit Size (Length, 73.77 mm; Breadth 77.68 mm) were observed in Gale Gala on M9. Further, higher Plant Spread E-W (125.00 cm) and fruit weight (218.23 g/fruit) were observed in Auvil Early Fuji. Studies have shown that all three pollinizer cultivars performed similarly with a non-significant difference, yet Redlum Gala/M9 performed better amongst the cultivars studied and it may be recommended to grow under high-density plantations in cold temperate conditions of Kinnaur, Himachal Pradesh.

Transgressive segregation and gene regions controlling thermotolerance of fruit set and pollen germination in Capsicum chinense

Breeding for thermotolerance in processes determining fruit set and pollen germination is increasingly needed as global warming progresses. We previously reported good yields at high temperatures from the F1 hybrid of the Capsicum chinense cultivars ‘Sy-2’ and ‘No. 3686’, both of which yield poorly at high temperatures. Moreover, the percentages of fruit set at high temperature in the F2 population segregated quantitively. In addition, percentages of fruit set in some F2 individuals exceeded those of the F1 hybrid. Analysis of the F2 population using double-digest restriction site-associated DNA sequencing (ddRAD-Seq) shows that the percentage of fruit set under high temperature is strongly associated to single nucleotide polymorphisms (SNPs) in a certain gene region of chromosome 6 and weakly associated to a gene region on the chromosome 3. Furthermore, the pollen germination rate is strongly associated to SNPs of the same regions on chromosomes 3 and 6. Analysis of the genotypes and traits in another F2 population shows that the genotype determined by the cleaved amplified polymorphic sequence marker designed on the candidate gene region is associated to the percentage of fruit set and the pollen germination rate at high temperatures, supporting the results of ddRAD-Seq. The presence of alleles from both the gene regions of chromosome 3 from ‘No. 3686’ and chromosome 6 from ‘Sy-2’ increased the percentage of fruit set additively. We suggest that genes controlling fruit set and pollen germination at high temperature are located in these two gene regions.

Studies on Phenology and Reproductive Biology of Khejri [Prosopis cineraria (L.) Druce

Background: Khejri [Prosopis cineraria (L.) Druce] belongs to the family Leguminosae and subfamily Mimosoideae. The rural communities encourage the growth of Khejri in their agricultural fields as it improves grain yield and storage biomass production. It is the true multipurpose species and also called as ‘Golden Tree of Desert’, ‘Kalpvriksha’ of the desert, ‘King of desert’, ‘Love Tree’, and ‘Pride of the Desert’. For any tree improvement programme, knowledge of phenology and breeding system is pre-requisite, which also helps in understanding the evolutionary dynamics of a species. The range of genetic variability is controlled by reproductive system, which in turn controls the adaptive change. Pollination mechanisms affect seed set, fertility, gene flow, breeding systems, hybridization and genetic constitutions of tree populations. Methods: In this investigation during 2014-15, ten trees of [Prosopis cineraria (L.) Druce] growing at the research area of Forestry Department of CCS Haryana Agricultural University, Hisar were randomly selected and phenological observations were made on the selected trees at different phenophases. Through selfing, breeding behaviour was examined, by covering the inflorescence with muslin cloth bags before opening. Approximately, an equal number of buds were kept open in close vicinity of the covered branch. Reproductive capacity was estimated from the percentage of fruit setting in marked inflorescence. Result: In present study of Prosopis cineraria, the average fruit set under self-pollination was nil whereas it was 2.03 per cent in open natural pollination. This study confirms previous studies that Prosopis cineraria is a cross-pollinated species.

Pollen tube growth and fruit set in quince (Cydonia oblonga Mill.)

Aim of study: To determine the self-compatibility level of eight quince cultivars.Area of study: The region of Belgrade (Central Serbia).Material and methods: Pollen tube growth in vivo and fruit set in two pollination variants (self- and open-pollination) were studied in eight quince cultivars. The quantitative parameters of pollen tube growth (average number of pollen tubes in the upper and middle third of the style, base of the style and in the ovary; the dynamics of pollen tube growth through these parts of the pistil) was determined using the fluorescence microscopy.Main results: The parameters of pollen tube growth and fruit set were primarily dependent on the genotype and variants of pollination. All studied parameters were significantly higher in the open-pollination variant compared with the self-pollination in all cultivars. In the self-pollination variant, ʻLeskovackaʼ and ʻVranjskaʼ had the highest number of pollen tubes that penetrated the ovary (2.10 and 0.54 in average, respectively), as well as the largest percentage of pistils with the penetration of pollen tubes in the nucellus of ovules six days after pollination (40.09% and 14.74%). Also, they had the highest percentage of initial fruit set (17.01% and 28.52%) and final fruit set (9.32% and 9.86%). Based on this, ʻLeskovackaʼ and ʻVranjskaʼ can be classified as self-compatible cultivars, while the others are self-incompatible.Research highlights: The majority of quince cultivars were self-incompatible. When establishing new orchards with these cultivars, care should be taken about the choice of pollenisers in order to achieve high yields.