Early Ripening Research Articles

Gene Expression in 1-Methylcyclopropene (1-MCP) Treated Tomatoes during Pre-Climacteric Ripening Suggests Shared Regulation of Methionine Biosynthesis, Ethylene Production and Respiration

The physiology of fruit ripening is defined as either ‘climacteric’ or ‘non-climacteric’. In climacteric fruit respiration during ripening increases until it reaches a peak, which is accompanied by an increase in autocatalytic ethylene production, whereas the respiration of non-climacteric fruit does not increase and they have no requirement for ethylene to complete their ripening. In an attempt to gain further insight into the involvement of autocatalytic ethylene production with the climacteric rise in respiration, tomato fruit were harvested at three defined stages of maturity prior to the climacteric peak (mature green, breaker, and early orange) and immediately exposed to the gaseous molecule 1-methylcyclopropene (1-MCP). The gene expression profile at each of these stages was monitored after 24 h, using an Affymetrix tomato microarray chip. This approach enabled us to identify ethylene responsive genes that are commonly regulated at early stages of ripening, as well as new candidate genes. In addition, 1-MCP treatment affected the levels of metabolites related to methionine biosynthesis. Methionine feeds climacteric ethylene production and we found that promotors of the genes of enzymes that catalyze the production of homoserine and homocysteine (aspartokinase/homoserine dehydrogenases and cystathionine beta lyase, respectively), precursors in the methionine pathway, contain the AtSR1 binding motif. This binding motif is recognized by ethylene activated transcription factors, hence indicating a role for ethylene in methionine synthesis during early ripening, explaining the autocatalytic ethylene production during subsequent ripening stages.

Sources of Economically Valuable Features for Selection of Vigna (Cowpea) in Conditions of Absheron Peninsula

Background: In recent years, large areas are periodically exposed to drought due to the climate change towards warming. In this regard, there is a need to expand the area of cultivation of drought-resistant leguminous crops. One of these species of interest for cultivation in the central lowlands of the Republic of Azerbaijan, where bean crops are greatly suppressed, is vigna. To date, this culture is not widespread, its biological and energy potential is underestimated. Therefore, the study of morphological and biological characteristics of promising varieties of cowpea in the region and a comprehensive study of the genetic resources of the culture is relevant. The purpose of the research is to study the cowpea collection, to identify forms with economically valuable traits and to create on their basis a new highly productive, technologically advanced, valuable with its quality vigna grain for a selection in the conditions of the Republic of Azerbaijan.Methods: The studies were conducted in 2007-2018 at the Institute of Genetic Resources (IGR) of the National Academy of Sciences (NAS) of Azerbaijan. 33 samples were used as research material: 9 of them were local forms and 24 were samples obtained from VIR. The vegetation period and resistance to diseases have been studied and the productivity and structure of the harvest have been analyzed. Result: As a result of research, the most high-yielding and high-quality samples K-269, K-257, AzeVÝG-2, K-271, K-262, AG-340 were revealed in the studied vigna samples. During the implementation of the breeding program using the results, we have developed a new early ripe, drought-resistant, heat-resistant, disease-resistant and high-yielding variety Ayla by the method of repeated individual selection from the VIR collection. These studies are an important initial study for the subsequent production of new varieties. We hope that this will lead to an increase in the acreage of cowpea in the Republic of Azerbaijan.

Diversity and Local Coadaptation of Escherichia coli and Coliphages From Small Ruminants.

Bacteriophages are highly specific predators that drive bacterial diversity through coevolution while striking tradeoffs among preserving host populations for long-term exploitation and increasing their virulence, structural stability, or host range. Escherichia coli and other coliform bacteria present in the microbiota of milk and during early ripening of raw milk cheeses have been linked to the production of gas, manifested by the appearance of eyes, and the development of off-flavors; thus, they might cause early blowing and cheese spoilage. Here, we report the characterization of coliphages isolated from manure from small ruminant farms and E. coli strains isolated from goat and sheep raw milk cheese. Additionally, the virulence and host range of locally isolated and laboratory collection phages were determined by comparing the susceptibility of E. coli strains from different sources. In agreement with the high genetic diversity found within the species E. coli, clustering analysis of whole-cell protein revealed a total of 13 distinct profiles but none of the raw milk cheese isolates showed inhibition of growth by reference or water-isolated coliphages. Conversely, 10 newly isolated phages had a broad host range (i.e., able to lyse ≥50% of bacterial hosts tested), thus exhibiting utility for biocontrol and only one cheese-isolated E. coli strain was resistant to all the phages. Whereas there was a high positive correlation between bacterial susceptibility range and lysis intensity, the phages virulence decreased as range increased until reaching a plateau. These results suggest local gene-for-gene coevolution between hosts and phages with selective tradeoffs for both resistance and competitive ability of the bacteria and host-range extension and virulence of the phage populations. Hence, different phage cocktail formulations might be required when devising long-term and short-term biocontrol strategies.

Physicochemical Characteristics and Superficial Damage Modulate Persimmon Infestation by Drosophila suzukii (Diptera: Drosophilidae) and Zaprionus indianus.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) and Zaprionus indianus Gupta (Diptera: Drosophilidae) were recently observed co-infesting persimmons in Brazil. We evaluate the infestation susceptibility of persimmons at different ripening stages (unripe, UN; early ripe, ER; orange ripe, OR, and overripe, OV) by D. suzukii and Z. indianus in the field and laboratory conditions. Additionally, we determined the influence of physicochemical characteristics (e.g., resistance to penetration force, fruit skin color, acidity (pH), TSS concentration, total titratable acidity [TTA]) and the type of damage that facilitates infestation by D. suzukii or Z. indianus. In the field, the natural infestation capacity and biological development of D. suzukii and Z. indianus were verified in whole fruits at the ripening stages ER, OR, and OV. The natural infestation was directly related to the physicochemical characteristics of the fruits (resistance to penetration force, pH, and total soluble solids). In the no-choice bioassay, the oviposition rate of D. suzukii did not differ between the ripening stages of the fruit. However, in the choice bioassay, there was a higher preference for oviposition in OV fruits. Regarding Z. indianus, the highest preference for oviposition was observed in OR and OV fruits in both bioassays. The presence of mechanical damage did not increase the susceptibility of the fruits to D. suzukii. However, it favored the oviposition of Z. indianus in OR and OV fruits. The damage caused by D. suzukii or mechanical damage favored the infestation by Z. indianus. This is the first report of the capacity of D. suzukii to infest whole persimmons in Brazil.

Fruit quality and biochemical characteristics of new early ripening apricots of Turkey

In this study, the important fruit quality characteristics of 11 early ripening and promising apricot hybrids and reference cultivars recently developed in Turkey were analyzed. A large variation was observed between the genotypes in terms of fruit size (fruit weight ranged from 34.28 to 72.53 g). The total soluble solids which is one of the significant fruit quality parameters for the table apricots, was found between 10.07 and 18.27% and fruit flesh/kernel rate was between 9.6 and 18.42. Epicatechin, rutin, catechin, chlorogenic acid, epigallocatechin gallate and β-carotene were found to be the highest bioactive compounds. A large variation was also determined among the genotypes in this regard. ABP-4-23 and ABP-7-12 apricot genotypes were rich with respect to catechin, chlorogenic acid, epicatechin, rutin and β-carotene. The highest catachin and epicatechin contents were obtained in ABP-4-23 (176.76 and 517.45 mg/kg, respectively). In terms of β-carotene ABP-2-24 and ABP-1-18 presented the highest values (127.45 and 119.54 mg/kg, respectively). Fruit weight was found highly and positively correlated with kernel weight and total soluble solids (r = 0.65 and r = 0.61, respectively). Fruit weight was also found to be moderately correlated with rutin, quercetin, and β-carotene, while corrrelations was negative for rutin and β-carotene. Total acidity was moderately correlated with catechin, epigallocatechin gallate and β-carotene in positive way.

Study of some economically valuable characteristics of genotypes of cotton that was selected by photosynthetic test signs in combination with classical selection methods

The article discusses the main results of research on the study of 28 cotton genotypes obtained from crossing ecological and geographical distant parental forms based on the principle, a set of economically useful traits. According to the obtained data, introgressive hybrids were characterized by more early ripening, yield and fiber yield in comparison with the zoned Khisor variety, which was used as a standard. It was established that the highest yielding genotypes differed: ALC-86/6 x Dusti-IZ, Cocer-4104 x Sorbon, Cocer-4104 x Ziroatkor-64, Cocer-4104 x Dekhkon, NAD-53 x Ziroatkor-64, NAD-53 x Dusti-IZ, NAD-53 x Dehkon, DP-4025 x Ziroatkor-64, DP-4025 x Dehkon, NAK-99/1 x Ziroatkor-64, which have a total yield of 90.0-100.0 g/plant, and prefrost 64.5-71.3 g/plant, which significantly exceeds the standard Khisor variety (by 45.8-55.8 g/plant and 31.3-38.1 g/plant). The same pattern also manifests itself in the yield of fiber combinations: Cocer-4104 x Sorbon (44.0%), Cocer-4104 x Dehkon (44.0%), NAD-53 x Dusty-IZ (44.0%), Nazilli-84-S x Dehkon (44.0%), AC-4 x Dusti-IZ (43.8%), Nazilli-84-S x Ziroatkor-64 (43.5%) and NAD-53 x Ziroatkor-64 (43.1%), outstand with more significant indicators (by 7.9-8.8%.), relatively to the zoned Khisor cultivar.

Анализ наследования окраски перикарпа и других признаков у гибрида риса Кубояр × Гагат

Abstract. Rice can form not only white, but also red, brown and black grains. In black rice, pericarp grains contain anthocyanins, which have antioxidant activity and are beneficial to human health. The purpose of the work is to study the inheritance of the black color of the pericarp and other qualitative traits in the intersubspecific hybrid of rice Kuboyar × Gagat, the selection of the best recombinant forms combining early ripeness, a compact erect panicle and black grain, the creation of the source material for practical selection. Methods The studies were carried out on hybrids of the first and second generation from crossing a white-grain variety of rice Kuboyar with black-grained Gagat in 2018–2019 in the Separate Division “Proletarskoye” of the Rostov Region. Results. A genetic analysis of the inheritance of the duration of the growing season, qualitative signs of coloring of flower scales and rice grains, and spinousness was carried out. In the second generation, 54 photosensitive non-flowering plants and 128 normal ones broke out, which indicates the interaction of four dominant genes in the genotype. The splitting according to the color of the pericarp was carried out according to the trihybrid scheme according to the type of com-plementarity in the ratio of 27 black: 21 brown: 16 white. The black color of the pericarp was formed when three dominant genes Kala1, 3, and 4 were present in the genotype, brown was determined by the Kala4 gene, and white by the remaining combinations of genes. According to the color of flowering scales, the cleavage occurred according to the digrid pattern: 9 black: 3 yellow with black apiculus: 4 straw yellow. Although the parental varieties were boneless, 39 spinous forms appeared in F2 with three complementary dominant genes An-a, An-b, An-c and inhibitor I, the remaining 89 plants were boneless. The best recombinant forms were selected, combining the optimal values of plants and panicles and black grain, the source material for practical selection was created.

Hybrid sorrel: cultivation potential and use as a novel non‐food multipurpose crop

AbstractHybrid sorrel is a perennial crop whose benefits include good wintering, early ripening, and relatively high biomass and energy yields. The average yields are usually in the range from 4 to 10 t ha−1 dry matter (DM) per year. Based on a long‐term study, a significant fertilization effect on hybrid sorrel yield was found. The crop establishment in spring is preceded by plowing in autumn. Hybrid sorrel can be harvested in the year following the establishment. As a perennial crop, hybrid sorrel provides ecosystem services to a greater extent than first‐generation annual crops. They are, for example, habitat functioning, air regulation, biodiversity conservation, anti‐erosion effect, and groundwater protection. After cultivation, it can leave up to 60 t ha−1 of slightly mineralizable organic matter in the soil. Hybrid sorrel's drawbacks include low resistance against weeds and sensitivity to drought damage. According to the available data, this hybrid sorrel is one of the most promising energy crops in the temperate zone. It is suitable for both combustion and biogas production. In biogas production, sorrel produces a total methane yield of about 2500 to 3500 mN3 ha−1, and as a biofuel for combustion it shows a relatively high DM calorific value, of about 18 MJ kg−1. Alongside its use for energy and fodder purposes, it can be cultivated to produce medicines and unique building materials. It can also be used for the phytoremediation of contaminated soils. © 2020 Society of Industrial Chemistry and John Wiley & Sons Ltd

RNA-Seq profiling reveals the plant hormones and molecular mechanisms stimulating the early ripening in apple

Fruit development and ripening are essential components of human and animal diets. Fruit ripening is also a vital plant trait for plant shelf life at the commercial level. In the present study, two apple cultivars, Hanfu wild (HC) and Hanfu mutant (HM), were employed for RNA-Sequencing (RNA-Seq) to explore the genes involved in fruit ripening. We retrieved 2642 genes, differentially expressed in HC and HM apple cultivars. Gene ontology (GO) analysis revealed the 569 categories, significantly enriched in biological process, cellular component, and molecular function. KEGG analysis exhibited the plant hormone transduction and flavonoid-anthocyanin biosynthesis pathways, might be involved in the fruit ripening and anthocyanin biosynthesis mechanism. A cluster of 13 and 26 DEGs was retrieved, representing the plant hormones and transcription factors, respectively, that may be important for early ripening in HM genotype. This transcriptome study would be useful for researchers to functionally characterize the DEGs responsible for early ripening.

Genome-wide identification and characterization of long non-coding RNAs involved in grape berry ripening

BACKGROUND: Long non-coding ribonucleic acids (lncRNAs) have been linked to many important biological processes, including fruit ripening. “Fengzao” is an early-ripening bud mutant of “Kyoho” that matures nearly 30 days earlier. However, the molecular networks controlling early ripening in Fengzao are still poorly understood in comparison to those in Kyoho. OBJECTIVE: The aim of the study was to gain a better understanding of the regulatory role of lncRNAs in the early ripening of grape berries. METHODS: The RNA-sequencing approach and quantitative real-time polymerase chain reaction validation were employed to identify lncRNAs and profile their expression patterns during berry development. RESULTS: In total, 24726 lncRNAs were identified, of which 19699 were differentially expressed (DE-lncRNAs) between developmental stages. The target genes of these lncRNAs and their regulatory relationships were predicted. The oxidoreductase activity, plant–pathogen interaction, plant hormone signal transduction, and flavanol biosynthesis pathways were enriched in the target genes of DE-lncRNAs, and six key lncRNAs (TCONS_00221683, TCONS_00684459, TCONS_00022149, TCONS_00167247, TCONS_00258125, and TCONS_00261813) were identified that may regulate the early ripening of grape berries. CONCLUSIONS: The results contribute to the understanding of the role of lncRNAs in early ripening of grape berries and will provide new insights for molecular breeding of grapes.

Use of the collection of the buckwhears genus in breeding programs

Aim. Using the hybridization method on the basis of the ecological and geographical principle of parental pairs selection, to create a new source material in the selection of buckwheat and conduct a comprehensive assessment of it. Methods. Testing, material evaluation, analysis of plants, yield and grain quality were carried out in accordance with the generally accepted methods of the State variety testing. Results. A new source material was created and evaluated in the selection of buckwheat based on the attraction to the hybridization of samples from the collection of the buckwheat genus, in particular, varieties Snezhen, Botansoba, Nokheda, Prymorska 7, collection sample No. 4013, Victoria Podilska, Belorussian early ripening, Arosa. Hybrid samples are compared with the Victoria standard variety. It was revealed that direct and reverse hybrids of the first generation from crossing varieties: Botansoba and Snezhen, Snezhen and Victoria Podilska, Nokheda and Snezhen are characterized by higher yields by 0.38–0.80 c/ha compared to the standard. Conclusions. We plan to continue testing the best breeding numbers in the following nurseries of the breeding process. Better with biometric and yield indicators, we plan to use breeding numbers in the breeding programs of the Scientific Research Institute of Cereal Crops of the PDATU. Keywords: hybridization, growing season, biometric parameters, yield.

The main results of work on the selection of gourds in the Volgograd Trans-Volga region

Relevance. One of the main methods for solving the problem of providing the population of the Russian Federation with vegetable and melon products is the development of selection and seed production. The creation of new competitive varieties and hybrids will enable the vegetable industry to transfer to a qualitatively new level of development.Material and methods.The object of research is new varieties and hybrids of watermelon, melon and pumpkin, created at the Bykov experimental station in the rainfed conditions of the Volgograd TransVolga region. Methods of creation are intervarietal and interlinear hybridization. Results and conclusions.As a result of breeding work at the station, a number of varieties and heterosis hybrids of melons and gourds were created, which significantly expanded the assortment of the melon breeding industry. Over the past 5 years, 4 varieties of watermelon, 2 heterotic hybrids of watermelon, 3 varieties of melon and 1 grade of pumpkin have been included in the State Register of Breeding Achievements. The assortment of new varieties varies in terms of ripening, dry matter content, shape and color of the fruit background, as well as in color and pulp consistency. The length of the growing season of the created varieties and hybrids of watermelon ranges from 63 days in early ripening (Duet F1, Temp F1, Meteor) to 85 in the mid-ripening variety Malachite. The highest solids content of the new variety of watermelon Medunok is up to 14%. Among melon varieties, the shortest growing season is characterized by the Comet variety up to 70 days. All varieties have a high solids content of 14.0-19.0% and a thick flesh. Promising pumpkin varieties are distinguished by a bright coloration of the pulp, a high carotene content and a long storage period. Thus, the introduction of new varieties of gourds in commodity and home garden melon farming will allow the conveyor growing of products, increase the product mix and the period of consumption of fresh produce.

Adaptive ability and stability genotypes of vegetable peas of different ripeness groups

Relevance.The aim of the work is to define the adaptive ability and environmental plasticity of pea genotypes of different ripeness groups which were selected in Krymsk EBS VIR Branch in special conditions of Krasnodar region.Materials and methods.Eleven pea varieties and one pea strain were sown for studying in fields of Krymsk EBS VIR Branch in 2013-2017. The area of the plot was 10 m2. Each variety was sown three times. The recording of the harvest was made in period of industrial ripeness. The share of influence of different factors on the yield of pea was defined with the help of mathematical methods. The differential ability of environmental and adaptive ability of genotypes, stability and environmental plasticity were also defined.Results.2013 was the most unfavorable year because of the bad weather conditions. That year the pea yield was only 5/1 tons per hectare. We detected a great influence of the environmental factors (38%), the genotype factors (31) and their cooperative factors (27) on the yield of pea. The main differential ability of environmental was detected in 2016 and 2016. There were average conditions in 2014. During all years of studying there was a high effect of environmental destabilization which showed the great difference between the yields of the different genotypes. The following genotypes were found: the genotypes with a high total adaptive ability – Kudesnik 2, Vesta (k-9352) Berkut (k-8856), G-344/16; stable genotypes – Krasavchik (k-9449) and Istok (k-9353); the genotypes with an environmental plasticity – Alpha (k-7071), Vesta (k-9352), Parus (k-9350), G-344/16. The varieties which were found for breeding purposes on the totality of different characteristics of adaptability, stability and environmental plasticity are Prima (o155213) of a very early ripeness group, Vesta (k-9352) – medium-early, Parus (k-9350, leafless) –medium and the G-344/16 – medium-late.

Supplemental irrigation impact on yield and yield quality parameters of rapeseed

AbstractDryland winter rapeseed (Brassica napus L.) produced in the semi‐arid regions of Turkey has variable yields. Supplemental irrigation alleviates the adverse effects of soil moisture stress on yield during drought periods. To determine the influence of irrigation timing on yield stability, a 3‐yr, on‐farm irrigation experiment was conducted to determine the effects of supplemental irrigation on rapeseed yield and yield components in a semi‐arid environment. The field experiment considered the influence of six irrigation quantities applied at three growth stages (vegetative, flowering, and early ripening) on rapeseed yield and quality. Supplemental irrigation improved rapeseed yield compared with cultivation under rainfed conditions throughout the three experimental years. Although the greatest seasonal evapotranspiration and rapeseed yields were observed with full irrigation, the highest economic rate and most efficient irrigation rate were for the optimum level to be applied at flowering. Protein content, oil content, and fatty acids increased with irrigation and were highest for the full‐irrigation treatment. Irrigation should be applied when 50% of available soil moisture has been consumed in the effective root zone at the early flowering stage. This timing enhances the water use efficiency and yield potential of rapeseed without reducing quality and could be highly beneficial for semi‐arid regions.

Posibles efectos del cambio climático en la región productora de cacao en Tabasco, México

La producción de cacao en México ubica al país como uno de los principales productores a nivel mundial. Tabasco es la entidad que mayor superficie destina a su producción, con cerca de de 40,869 ha, concentrándose principalmente en la subregión de la Chontalpa. El objetivo de este trabajo es calcular los indicadores agroclimáticos para el ciclo reproductivo del cacao y sus posibles alteraciones bajo escenarios de cambio climático (RCP4.5)[1] en el horizonte de tiempo 2015-2039. Para la floración del cacao, en la región productora de Tabasco, se requiere un promedio de 926 unidades fototérmicas (u.f.), 1,130 u.f. para la fructificación, y 1,047 u.f en la etapa de madurez, además, se requieren aproximadamente 2,760 unidades calor (u.c.) para completar el ciclo reproductivo, y nueve meses de periodo húmedo con menos de dos meses de déficit hídrico en el suelo. Por lo que las condiciones climáticas en la región de la Chontalpa son las adecuadas para el ciclo fenológico del cacao. Los resultados de los escenarios de cambio climático muestran que las temperaturas aumentarán en ese lapso en promedio 1°C, mientras que las precipitaciones disminuirán entre 100 y 200 mm del total anual, con 4 a 5 meses de precipitaciones menores a 100 mm. Este escenario climático ocasionaría un aumento en la evapotranspiración potencial (ETP) entre 3 y 5 meses (entre enero y mayo) y los posibles efectos del déficit hídrico por efectos del cambio climático en la fenología del cacao son: la inhibición de la floración, la producción de vainas más pequeñas y la madurez temprana del fruto.
 
 [1] La ruta de concentración representativa (RCP) 4.5 es un escenario que estabiliza el forzamiento radioactivo a 4.5 W m − 2 en el año 2100 sin exceder ese valor. Simulado con el Modelo de Evaluación de Cambio Global (GCAM), RCP4.5 incluye emisiones globales a largo plazo de gases de efecto invernadero, especies de vida corta y uso de la tierra en un marco económico global.

Features and properties of tangerine hybrids derived from distant hybridization (Citrus var. unshiu×Poncirus trifoliata)

Among citrus crops in the subtropical zone of the of the Russian Federation Black Sea coast of Krasnodar Territory, only tangerines can be grown (Citrus reticulata Blanco var. unshiu Tan.). The expansion of planting is hindered by poor winter hardiness, that’s why breeders are faced with a task of creating new forms of mandarin that are maximally adapted to the extreme climatic conditions of the region. By using of a distant hybridisation it is possible to create such forms. Purposeful distant hybridization allows transferring the properties of one genus to another, which is leading to phenotypic and genotypic changes in hybrid generation. The article emphasizes the importance of distant hybridization. For the period 1995-2019, distant, recurrent and inter-hybrid hybridizations were carried out to create a new hybrid fund. The results of 19 combinations of crossing by using Poncirus trifoliata Raf., and hybrids which were obtained with the participation of this genus, as well as hybrid species: C.×insitorum, C.×citrangeqwa and the genus Fortunella Sw. Expanded forms were selected for further breeding with an early term of fruit ripening (I decade of October): YuМR-97; YuКR-22; ККR-27; ККR-22; МRКR-97-25; МRКR-97-25-1; КRМR-25-97, with later ripening (II decade of October: КVI-1, КVI-3, YuI-12 received with C. insitorum. Also with late maturity hybrids were revealed: КРF-25; КРF-22; МРF-97; TsКR-25; YuTs-8 with the immixture of Fortunella margarita and C. citrangeqwat. From recurrent and inter-hybrid hybridization were marked out promising forms of mandarin with positive features such as early ripening, average fruit mass and a high tasting assessment. The greatest breeding value is represented by hybrids derived with the immixture of the most frost-resistant ccongeners of the citrus Poncirus trifoliata, however, from 5.0 % to 6.25 % of promising samples were selected in these families. All forms have breeding value for further work on creating winter hardiness varieties of mandarin.

ПРИМЕНЕНИЕ ГЕРБИЦИДОВ НОВОГО ПОКОЛЕНИЯ ПРИ ВОЗДЕЛЫВАНИИ КУКУРУЗЫ В ПРЕДГОРНОЙ ЗОНЕ РСО – АЛАНИЯ

The article discusses the results of studying the effectiveness of using new generation herbicides: both applied before the emergence of corn seedlings ("Merlin" (150 g/ha); "Cassius" (50 g/ha)), and by seedlings ("Elumis" (1.0–2.0 l/ha)) – on crops of three maize hybrids. The studies were carried out in 2017–2019. The objects of research were maize hybrids of various early ripening (originator Kabardino-Balkaria Research Institute of Agriculture) – Kabardinskaya 3812 (late ripening), Camilla SV (mid-late), and white grain food corn Bella 451 (cultivated not only for obtaining varietal seeds, fodder, but also to meet the food needs of the indigenous population). Flour and cereals from white grain corn are used in most ethnic cuisines of the North Caucasus. In this regard, it is very important to put into production, along with the yellow grain forms used for fodder, highly productive varieties and hybrids of white grain corn for food purposes. The variety is medium late and food grade. The purpose of the research was to establish the level of harmfulness of weeds and their death rate at different periods of their introduction, as well as to determine their effect on the growth, development and yield of corn grain. The scientific novelty lies in the fact that in the conditions of the foothill zone of the Republic of North OssetiaAlania, studies have been carried out to establish the optimal terms and methods of applying herbicides in the fight against weeds when cultivating new highly productive corn hybrids. As a result of the studies, it was found that the treatment of the soil with the herbicide "Elumis" was more effective in comparison with the control option. At the same time, the grain yield was: for the Kabardinskaya 3812 hybrid 8.7 t/ha – on an unfertilized background, 12 t/ha – on a fertilized one; for the hybrid Camilla SV – 8.5 t/ha on an unfertilized background, 11.7 t/ha – on a fertilized one; the Bella 451 hybrid has 7.0 t/ha – on an unfertilized background, – 9.9 t/ha – on a fertilized one. The responsiveness of the Kabardinskaya 3812 hybrid to the application of herbicides was more effective than that of other studied hybrids.

Influence of post-harvest application of ethrel and paper wrapping on physical parameter and ripening of papaya (Carica papaya l.) Cv. Madhu Bindu

Papaya (Carica papaya L.) is an important and a very popular fruit crop of the tropical and subtropical areas in the world. The experiment was conducted to study the “influence of post-harvest application of ethrel and paper wrapping on papaya (Carica papaya L.) cv. Madhu Bindu” during kharif, 2017 at Department of Horticulture, B. A. College of Agriculture, Anand Agricultural University, Anand(Gujarat). The experiment was framed in completely Randomized Design with factorial concept replicated thrice with ten treatment combination. The treatment were comprised of five different concentration of ethrel (0 mg/l, 500 mg/l, 750 mg/l, 1000 mg/l and 1250 mg/l) along with paper wrapping (with paper wrapping and without paper wrapping). Fruit dipped in ethrel @ 1250 mg/l shows early ripening. Significantly minimum PLW (%) and spoilage (%) while, maximum firmness and shelf life were observed with no-ethrel treatment (0 mg/l). In case of paper wrapping significantly maximum firmness, minimum PLW and early ripening was observed with paper wrapping while, significantly minimum spoilage and long shelf life was observed in non-wrapped fruit.

Methods of managing the agricultural background of cotton and technical means for their implementation

In the complex of measures aimed at reducing the laboriousness of cultivating and growing high yields of raw cotton, a major role is given to further improving the technology and means of mechanizing cotton sowing. In recent years, rainy weather has been observed during the period of sowing cotton, as a result of which the germination of cotton seeds is significantly delayed. When showers, puddles form on the traces of the seeder, which leads to rotting of the seeds, as a result of which repeated sowing is carried out. When cultivating cotton on the ridges, in accordance with the theoretical foundations of soil cultivation, a favorable composition of the arable layer is ensured for a long period of cotton growing. This contributes to friendly shoots, good plant development and a high yield of raw cotton with early ripening, moisture accumulation on the ridges eliminates soil pollination, destruction of the structure, and formation of soil crust. Using the drip irrigation system allows to provide plants with water and fertilizers, where necessary, at the right time and in the right amount.

Infestation indices and characterization of injuries of Drosophila suzukii Matsumura (Diptera: Drosophilidae) in Barbados cherry

Females of Drosophila suzukii Matsumura (Diptera: Drosophilidae) have a serrated ovipositor that causes severe physical damage to soft fruit. This behaviour results in the early ripening and accelerated rotting of infested fruit. In addition, feeding by larvae softens of the fruit peel, causing in a depreciation in commercial value. In this study, results of infestation indices, pupal viability, egg-adult period, degradation time of infested fruit, and description of physical injuries caused by oviposition and larval feeding of D. suzukii in Barbados cherries (Malpighia emarginata DC., Malpighiaceae) are described. Overall, our results and discussion contribute to the understanding of the status of D. suzukii as an insect pest of the Barbados cherry.