Thermal indices in relation to crop phenology and fruit yield of apple

Field experiments were conducted on gravel sandy soil of research farm of Horticultural Research Station, Seobag in Kullu valley with ten varieties of apple for three seasons (2008-2010). In the first crop season all the varieties matured within 157-188 days, while in the second and third seasons the crop matured with 159-179 and 156-187 days, respectively. The mean GDD accumulation from bud burst to fruit set was from 382 to 419° D and to maturity 2310 to 2957° D. The varieties, Mollice and Starkrimson consumed the lowest and highest GDD for attaining physiological maturity in different seasons among all varieties. But Commercial and Tydeman consumed the lowest and highest GDD for fruit setting. The photo thermal index (PTI) in all the varieties and seasons varied from 7.2 to 16.8 and 13.2 to 18.4° D/day at flowering and reproductive stages respectively.

Effects of salicylic and benzoic acid on yield and yield components of moisture stressed tomato (solanum lycopersicun l.) at Kadawa Sudan Savannah

Salicylic acid and Benzoic acids are antitranpirants usually used to reduce the rate of moisture loss and increase productivity of irrigated crops. To test antitranspiracy of Salicylic and Benzoic acids, field experiments were conducted during the two successive dry Seasons of 2011/2012 and 2012/2013 at the Agricultural Research Station Farm, Kadawa (11̊ 38ʹ 40.3ʺ N,8̊ 25ʹ3.9ʺ E) 498m elevation above sea level. The aim was to study the effects of antitranspirants and moisture stress on crop growth and development stages of tomato. The treatments consisted of two antitranspirants at four different concentrations of 0, 200, 400 and 600 ppm, and three moisture stress stages, vegetative, flowering and fruit setting. Antitranspirants and moisture stresses were assigned to the main plot and concentrations were used as sub–plot treatment. These were replicated three times and laid out in a split-plot design. The gross plot size was 3.6m x 3.0m (10.8m2) consisting of 6 rows of 3m length, while the net plot size was 1.2m 1.8m (2.16 m2) consisting of 2 inner most rows. Data were taken on tomato growth and yield attributes. Data generated were analysed using statistical analytics software (SAS). The results of the study revealed that application of both Antitranspirants enhanced growth and yield components such as fruit diameter, number of fruits plant1, average fruit weight, marketable fruit yield and total fruit yield of tomato. Significant interactions between and among the factors were also recorded for fruit diameter, number of fruits plant-1 marketable fruit yield and the total fruit yield. Application of 200 and 400 ppm of of Salicylic acid at fruit setting produced the highest total fruit yield (6.66 tha-1) which was statistically similar to 600 ppm of Benzoic (6.10 t ha-1) at flowering while the control had the lowest. Total fruit yield was positively and significantly correlated with number of fruit plant-1 and average fruit weight. Number of fruits plant-1 was found to have the highest direct contribution to the yield. Flowering and fruiting stages were found to be the critical growth stages for moisture stress of tomato. Foliar application of 400 ppm of Salicylic acid at fruit setting stage appeared to promote tomato yield in the study area.

Reproductive ability of black currant cultivars after pollen cryopreservation in liquid nitrogen

Background. Studying the reproductive ability of black currant cultivars after long-term cryopreservation of their pollen in liquid nitrogen is very important for plant diversity conservation and for the effectiveness of breeding efforts.Materials and methods. Five black currant cultivars served as the material for the research. The viability of black currant pollen after cryopreservation in liquid nitrogen was analyzed. Pollen viability was tested on an artificial medium containing 10% of sucrose and 0.8% of agar. The viability of pollen was tested on the black currant collection at Pushkin and Pavlovsk Laboratories of VIR. The cultivar ‘Andreevskaya’ (k-15630) was pollinated with pollen stored for one year in liquid nitrogen (–196°C) as well as with fresh pollen (control test).Results and conclusion. After 12 months of conservation under ultralow temperatures there was a change in the level of pollen viability depending on the genotype: it varied from 10.4% (cv. ‘Pozdnyaya poslevoennaya’, k-7654) to 50.4% (cv. ‘Kriviai’, k-42517), while its mean value was 0.9% higher than the mean initial viability. The fruit setting rate in the control option was 81.3–94.2%. When pollinated with pollen kept in liquid nitrogen for one year, the fruit setting rate varied from 69.2% (‘Kacha’, k-44185) to 93.3% (‘Belorusochka’, k-41978); the remaining cultivars (‘Pozdnyaya poslevoennaya’; ‘Chereshneva’, k-42481; and ‘Kriviai’) demonstrated intermediate values of this indicator, i.e., the reproductive ability of pollen after cryopreservation was high even despite its low viability. As for the fruit weight, no differences were shown by cvs. ‘Kacha’, ‘Chereshneva’ and ‘Kriviai’ in both pollination options, while this indicator in cvs. ‘Belorusochka’ and ‘Pozdnyaya poslevoennaya’ was lower than the control by 0.31 and 0.24 g, respectively.

Description of buckwheat cultivars from Belarus and Ukraine in the environments of Leningrad Province

Background. Buckwheat is an extremely valuable groat crop in demand both in Russia and abroad. The buckwheat collection held by VIR is the largest in the world. Studying and systematizing knowledge about the conserved diversity of the genus Fagopyrum Mill. representatives cannot be efficient without switching to the use of the most detailed descriptors containing plant characters least dependent on differences in growing conditions.Materials and methods. Seventeen buckwheat cultivars from Ukraine and Belarus and two references from Russia were studied in Leningrad Province. The methodological basis of the study included the IPGRI buckwheat descriptors and personal recommendations of N. V. Fesenko. Statistical data processing was performed according to P. F. Rokitsky.Results. The cultivars formed their typical plant habitus and demonstrated good fruit setting − an average score was 3.3–4.9 out of five. The determinant stem growth was observed in 10 cultivars. The stem developed 2.7−6.7 generative nodes and 4–6 vegetative ones, while 1.9–4.7 generative and 0.8−2.3 vegetative nodes were formed on the two upper branches.Conclusion. The study confirmed that medium-ripening buckwheat can be grown in Leningrad Province. The modal value of the number of vegetative nodes for the studied cultivars was 4−5, which is an indicator of intermediate ripening. The results of studying the metamerism of the stem and the two upper branches, expressed by modal values, were recorded in the “agricultural fitness” passport for the tested cultivars as follows: determinant stem; branching zone 4+1+2; fruit-forming zone 3+3+3; average score of fruit formation 4.8. The presented data format most fully characterizes a cultivar in terms of the potential of its earliness and productivity. Depending on the task, indicators for the main stem or for the two upper branches can be used. Recording values in the form of a formula is convenient and does not imply any other meanings.

Seaweed and microalgae as major actors of blue biotechnology to achieve plant stimulation and pest and pathogen biocontrol – a review of the latest advances and future prospects

Modern agriculture needs proper solutions to face the current trend of pesticides and fertilizers reduction. One of the available leverages to support this transition is the use of bioproducts that are more environmentally friendly and less hazardous for human health. Among them, blue biotechnology and more precisely seaweed and microalgae gain interest every year in the scientific community. In agriculture, seaweeds (Macroalgae) have been used in the production of plant biostimulants while microalgae still remain unexploited. Microalgae are widely described as renewable sources of biofuels, bioingredients and biologically active compounds, such as polyunsaturated fatty acids (PUFAs), carotenoids, phycobiliproteins, sterols, vitamins and polysaccharides, which attract considerable interest in both scientific and industrial communities. They affect agricultural crops for enhancement of plant growth, seedling growth. They can also improve nutrient incorporation, fruit setting, resistance properties against pests and diseases, improving stress management (drought, salinity and temperature). The present review aimed at the interest of blue biotechnology in agronomy, with a specific focus on microalgae, their biological activities and their possible application in agriculture as a potentially sustainable alternative for enhanced crop performance, nutrient uptake and resilience to environmental stress. This review does not only present a comprehensive study of microalgae as plant biostimulants but also as biofertilizers, with a particular emphasis on future challenges these solutions will have to deal with, microalgae being able to synthesize secondary metabolites with potential biopesticidal action.

Effect of plant growth regulators on two different types of eggplant flowers regarding style length and fruit setting

Aim of study: (i) to explore differences between eggplant flowers capable of setting fruit including long (LGs) and medium style flowers (MEs) and those which suffer from severe problems with fertility and fruit setting including short style ones (SRTs); (ii) to study the effect of plant growth regulators on floral morphology and fruit setting. Area of study: Isfahan University of Technology, Isfahan, Iran, 2017 and 2018. Material and methods: First the floral morphology and initial fruit setting of 13 eggplant genotypes from Iran were investigated. Then the differences between LGs and SRTs of two genotypes were explored. Finally, the effect of 1-naphthaleneacetic acid (NAA) and spermidine (Spd) on floral morphology and initial and final fruit setting of these two genotypes was determined. Main results: Results showed SRTs were not capable of fruit setting. Compared to SRTs, LGs had larger central canals, higher protein, total sugar, reducing sugar and K concentrations, as well as longer polar axis and pollen tubes and greater pollen viability. Although 1.5 mM Spd and 20 mg L-1 NAA resulted in increasing of LGs and MEs, and also total initial fruit set, surprisingly, no significant differences were observed in the final yield and final fruit set between the control and these treatments. Researching highlights: Since the rate of fruit dropping was higher in those treatments compared to the control, plants with more SRTs likely regulate their final load by abscising their flowers, and plants with more LGs regulate them by abscising their fruits.

Cucumber breeding lines are a prospective material for creating new varieties for open ground in southern Russia

The varieties and hybrids of cucumbers cultivated in the Astrakhan region are insufficiently productive and are largely affected by a number of diseases. The introduction of innovative developments into production, in particular, new varieties and hybrids of domestic selection, largely solves the problem of import substitution and food security. The goal is to use promising breeding lines and their offspring as genetic sources and donors when creating new varieties and hybrids for open field conditions in southern Russia.Methods. Experiments were carried out in the fields of Precaspian agrarian federal scientific center of the Russian academy of sciences, according to the methods used in the Astrakhan region. Within three years, 47 collection samples were tested.Results. The article presents the results of studying the 12 most promising ones, distinguished by a complex of valuable economic traits, in particular by yield, amicability of fruit setting, which are of interest for further breeding work. According to the results of the data obtained, we can say that the best were the lines: 13-88RZ, 13-101RZ, Gherkins, KRASTAVAC, Courage, Zina, they can be used to create new varieties and hybrids of cucumber as donors of a predominantly female type of flowering, harmonious yield.

Effect of Nutrient Management on Productivity and Quality of Acid Lime (Citrus aurantifolia swingle)

Acid lime (Citrus aurantifolia Swingle) is one of the commercial fruit crops which occupies an important place in the fruit industry, but yield levels of citrus orchards are still very low. An alternate nutrient management system could help in achieving a high yield and quality of acid lime. Thus, an investigation was undertaken on the “Effect of nutrient management on productivity and quality of acid lime (Citrus aurantifolia Swingle)” during 2016 – 2018. The experiment was laid out in randomized block design with twelve treatments, various organic manures, biofertilizers along with inorganic fertilizers including recommended dose of fertilization @ 100%, 75%, 50%, farm yard manure @ 100%, 50%, Vermicompost @ 100%, 50%, Biofertilizers (25 g Azotobacter + 25 g phosphate solubilising bacteria + 150 g vesicular arbuscular mycorrhizal) were applied. The yield and quality characters of acid lime were studied at vegetative and reproductive stages. The observations recorded viz., fruit setting (%), fruit diameter (cm), number of fruits per plant, fruit weight (g), yield per tree (kg) and yield per hectare (tonnes). The results revealed that plants treated with T12 ( 50% RDF+ 75% Vermicompost + Biofertilizers (25 g Azotobacter +25 g PSB +150 g VAM) was observed maximum fruit setting (%), fruit diameter (cm), number of fruits per plant, fruit weight (g), yield per tree (kg), yield per hectare (tonnes). The maximum net income (Rs. 281511.5 / ha) and benefit:cost ratio (4.72: 1) was observed in the treatment T12-50% RDF + 75% FYM + 75% Vermicompost + Biofertilizers (25 g Azotobacter + 25 g PSB + 150 g VAM) which was superior to other treatments.

Style length and flower morphology of three eggplant (Solanum melongena L.) cultivars from Iran affected by fruit load

<p>A common feature of eggplant is its heterostyly. Long-style flowers bear fruits whereas short style ones fail to do so. Heterostyly is influenced by some factors such as genotype, climatic conditions and fruit load. In this study three eggplant cultivars from Iran were cultivated under greenhouse condition. The influence of presence of fruit (two fruits and four fruits) or absence of that on style length and some other flower morphological was studied in three positions of single, basal and additional. The presence of fruit, specially four fruits reduced style length, stigma width as well as mass of flower, pistil and stigma compared to the control in all times during fruit growth, and after fruit harvest they increased again. Fruit load didn’t affect the number of stamen and stamen length. These effects were observed in all three positons of single, basal and additional flowers of all three cultivars. Generally this study showed that fruit load has decreasing effect on style length and size of flowers forming after fruit setting, which reversed after fruit harvesting.</p>