The floods in north India in 1988- Forecasting aspects

Severe floods/flash floods ravaged the States of Jammu& Kashmir, Haryana, Himachal Pradesh and Punjab during, (i) 2nd half of July and last half of August 1988. and (ii) 4th week of September 1988. They took place when heavy rains occurred in these States due to the interaction of mid-latitude westerly troughs with the monsoon pulses In the form of equatorial zones of maximum cloudiness (EZMC), located south of 20 N. Satellite pictures and synoptic charts suggest that: (a) The systems which formed in July-August 1988 were fed by moisture mainly from the Arabian Sea and had tropical characteristic, and (b) The systems which formed in SejJtember.198.8 had their moisture supply both from the Arabian Sea and the Bay of Bengal and were extra-tropical in character.. The paper describes two of these events in detail. The satellite picture3 show cloud formation resulting in heavy rains.

Ecological trial of the winter wheat varieties of the ARC “Donskoy” in the area of dark chestnut soils of the Volgograd region

The current paper has presented the trial results of the winter wheat varieties developed by the ARC “Donskoy” in 2018 -2020. Currently, the farmers have bred a lot of different wheat varieties, but they are not able to take into account all the peculiarities of their cultivation. The purpose of the current work was to study the features of the autumn and spring-summer vegetation periods of the winter wheat varieties developed by the ARC “Donskoy” in the area of dark chestnut soils of the Volgograd region. There have been selected 10 winter wheat varieties for the trials. The field trial was laid down on dark chestnut soils of the lands of the Serafimovichsky district in the Volgograd region. The study was carried out according to the generally accepted B.A. Dospekhov’s methodology. The field trials showed that the germination of winter wheat was influenced by a seeding depth, which was 7-9 cm. The best germination was found among the varieties ‘Asket’, ‘Etyud’, ‘Lilit’, ‘Donskaya Step’ and ‘Zhavoronok’. During the trials, the formation of a productive stand was greatly influenced by the weather (the length of a spring tillering period, precipitation in May), as well as the traits of the variety. The winter wheat varieties ‘Etyud’, ‘Shef’, ‘Donskaya Step’, ‘Krasa Dona’ were able to form a large number of productive stems under favorable weather conditions. Under insufficient moisture supply, the largest number of productive stems was formed by the varieties ‘Lidiya’ and ‘Lilit’. The highest tillering intensity during an autumn vegetation period was shown by the variety ‘Lidiya’ (4.7–6.2 shoots), including the varieties ‘Zhavoronok’ (4.2–5.4 shoots) and ‘Etyud’ (4.0–5.3 shoots). The largest productivity was produced by the varieties ‘Donskaya Step’ (4.97 t/ha), ‘Zhavoronok’ (4.95 t/ha), ‘Krasa Dona’ (4.90 t/ha) over three years.

Leaf surface index as an indicator of moisture responsiveness and drought resistance of winter bread wheat samples

The growth and productivity of drought-prone varieties are strongly influenced by the chlorophyll pigment content and the development of plants’ foliage. The current climate changing, characterized by long no-rain periods followed by short intense rainfalls, is forcing plants to adopt different strategies to cope with drought. The purpose of the current study is to estimate the effect of growing conditions on the indicators of the total leaf area, leaf surface index (LSI) of sowing, the concentration of chlorophylls (Chl) in the leaves and the yield of winter wheat, depending on the value of their moisture supply. There have been established that the leaf surface index change and the preservation of chlorophyll pigment in foliage during the vegetation period is closely related to plants’ drought resistance, soil moisture reserve and a genotype. Under conditions of insufficient moisture supply, the maximum values of the leaf surface index in the heading phase were formed by the varieties ‘Krasa Dona’ (5.99 r.u) and ‘Etyud’ (2.49 r.u.). The highest content of chlorophyll pigment, both in the heading phase and in the flowering phase, was identified in the varieties ‘Krasa Dona’ (3.7; 3.0 mg/100 g of raw material), ‘Etyud’ (3.4; 3.2 mg/100 g of raw material) and ‘Volny Don’ (3.2; 3.0 mg/100 g of raw material), respectively. Acording to the value of productivity, the reliably standard variety ‘Don 107’ has exceeded the varieties ‘Etyud’, ‘Krasa Dona’, ‘Asket’, ‘Volny Don’.

The effect of moisture supply conditions on productivity of winter bread wheat, sown after various forecrops in the southern part of the Rostov region

Weather and climatic conditions determine moisture supply, which is the main factor affecting winter wheat productivity in the area of unstable moisture. The current study was carried out on the experimental plot of the laboratory for cultivation technology of grain crops of the FSBSI Agricultural Research Center “Donskoy” in 2010–2020. The soil of the experimental plot was ordinary calcareous heavy loamy blackearth (chernozem). The humus horizon was powerful up to 140 cm. The humus content was 3.9%. The purpose of the study was to establish the moisture supply of winter bread wheat when cultivated according to various forecrops. There has been found that the autumn periods in the most years of study were arid with 37% of precipitation. Winter wheat plants from September to June were provided with 70% of precipitation, with a 1022.55 of air humidity deficit and 664.7 mm of water demand. There was found that, on average over the years of study, 88% of moisture supply promoted yielding of 7.03 t/ha of winter wheat sown in weedfree fallow. In order to yield a ton of grain there was required 591.7 m3 of total moisture. The share of precipitation in this moisture consumption was 84%, and the share of soil moisture was 16%. When sown after sunflower, moisture provision was 77%, and winter wheat yield was 5.32 t/ha. In order to yield a ton of grain there was required 657.3 m3 of total moisture, which was on 65.6 m3 more than in the variant with a weedfree fallow. The share of precipitation in this moisture consumption was 96%, and the share of soil moisture was 4%.

Vegetation Drought Vulnerability Mapping Using a Copula Model of Vegetation Index and Meteorological Drought Index

Since vegetation is closely related to a variety of hydrological factors, the vegetation condition during a drought is greatly affected by moisture supply or moisture demand from the atmosphere. However, since feedback between vegetation and climate in the event of drought is very complex, it is necessary to construct a joint probability distribution that can describe and investigate the interrelationships between them. In other words, it is required to understand the interaction between vegetation and climate in terms of joint probability. In this study, the possibility of drought stress experienced by vegetation under various conditions occurring during drought was investigated by dividing drought into two aspects (atmospheric moisture supply and moisture demand). Meteorological drought indices that explain different aspects of drought and vegetation-related drought indexes that describe the state of vegetation were estimated using data remotely sensed by satellites in parts of Far East Asia centered on South Korea. Bivariate joint probability distribution modeling was performed from vegetation drought index and meteorological drought index using Copula. It was found that the relationship between the vegetation drought index and the meteorological drought index has regional characteristics and there is also a seasonal change. From the copula-based model, it was possible to quantify the conditional probability distribution for the drought stress of vegetation under meteorological drought scenarios that occur from different causes. Through this, by mapping the vulnerability of vegetation to meteorological drought in the study area, it was possible to spatially check how the vegetation responds differently depending on the season and meteorological causes. The probabilistic mapping of vegetation vulnerability to various aspects of meteorological drought may provide useful information for establishing mitigation strategies for ecological drought.

Mechanism of The Summer Rainfall Variation in Transitional Climate Zone in East Asia From the Perspective of Moisture Supply During 1979-2010 Based On The Lagrangian Method

Transitional Climate Zone (TCZ) over East Asia, characterized by semi-arid climate, is ecologically fragile environment with limited water resources, making atmospheric moisture supply being the key influential factor. This study investigates the moisture sources of summer (JJA) rainfall in the TCZ over East Asia during 1979-2010 with the Lagrangian particle dispersion model. Seven moisture source regions and associated contribution are quantified: Eurasia continent to northwest of the TCZ (EC, 18.01%), central-eastern China (CEC, 17.14%), western Pacific Ocean (WPO, 7.46%), South China Sea and Indonesia (SCSI, 3.56%), Bay of Bengal (BOB, 2.55%), Arabian Sea (AS, 2.13%) and local evaporation (TCZ, 19.96%). The moisture contribution from ocean (16.06%) is less than those from the continent (55.11%), due to the great loss en-route. In particular, the local evaporation not only contributes the most moisture among 7 selected source regions, but also has the greatest influence in summer precipitation variability in TCZ. Furthermore, westerlies precipitation and monsoon precipitation are discriminated according to the dominant system of water vapor source regions. It is found that summer monsoon contributes most of water vapor (33.2%) to summer rainfall in TCZ, while only 18.01% comes from the mid-latitude westerlies dominant area. Finally, further analysis of dry and wet years shows that summer monsoon system also takes more responsibility for a drier or wetter summer in TCZ from the perspective of moisture supply, followed by local evaporation and mid-latitude westerlies.

The effect of tillering on spring wheat productivity in various agro-weather conditions

The current study was carried out on the basis of the Institute of Seed Production and Agrotechnologies, located in the Ryazan Region in 2010–2019, in order to determine the participation share of tillering shoots in the formation of spring wheat productivity in various agro-weather conditions. The objects of the study were the varieties ‘Lada’, ‘Agata’, ‘RIMA’, ‘Maestro’ developed by the Federal Research Agro-Engineering Center VIM. The mean productivity of the studied spring wheat varieties, depending on the level of moisture supply of the growing seasons, had a significant range of 2.20–5.29 t/ha. The mean density of the stems varied from 216 to 620 pcs/m2 among the varieties. The minimum value of 153–253 pcs/m2 was formed under severe drought conditions. When moisture supply improved, the indicator sharply increased in 2.6 times. There has been established that in more humid conditions (HThC 0.98–1.55) the plants were able to realize their potential tillering to a greater extent, the general indicators of tillering among the varieties ranged from 1.06 to 1.23 and 1.63 to 2.11. There was estimated an effect of secondary shoots on productivity, which was 35.2% on average in the trial, and from 10.6% to 48.3% depending on the genotype and environmental conditions. There has been found a shoot formation decrease in 2.4 times of the variety ‘Lada’ under a moisture deficit. There has been determined that the variety ‘RIMA’ had the lowest tillering coefficient for all vegetation periods, and grain weight per a main spike mainly contributed to its productivity. During the moisture deficit periods, the share of the effect of lateral shoots in the variety ‘Agata’ was at the level of mean values, and on 9.9% and 13.1% more than in the varieties ‘Lada’ and ‘RIMA’, respectively. The maximum value of the productivity on the lateral shoots was formed by the variety ‘Maestro’, the productivity share of the secondary shoots during all periods was higher than that of all varieties and amounted to 39.1–48.3%.

The effect of technology elements on weediness and productivity of brown mustard (Brassica juncea) sowings

Modern plant protection should be as environmentally friendly as possible, therefore, agrotechnical methods should form its basis. The current paper has presented the results of three-year study (2017–2019) of the effect of nitrogen fertilizers and seeding rates on the brown mustard productivity and its ability to suppress weeds. The study was carried out in the Central steppe of the Crimea on the southern low-humus blackearth (chernozem) by the researchers of the FSBSI “Research Institute of agriculture in Crimea”. The purpose of the current study was to determine the effect of nitrogen fertilizers and seeding rates on the productivity and competitiveness of brown mustard. There was found that the amount of weeds depends on the individual weediness of the field and the conditions of moisture supply of the year. By the time the mustard was harvested, the number of weeds increased by almost 1.5 times due to the emergence of new shoots of weeds during the ripening period of mustard. There has been presented the dynamics of dry weeds weight depending on the seeding rate. There has been shown that the growth and development of weeds depends on the density of the brown mustard sowings. With an increase in the seeding rate from 0.5 to 3.0 million pieces per hectare, the dry weeds weight decreased from 180.8 to 44.3 g/m2 on average over three years. An increase in the seeding rate from 2.5 to 3.0 million pieces per hectare did not provide a significant decrease in dry weeds weight. There has been established that the optimal seeding rate for growing brown mustard in the Crimean steppe is 2.5 million pieces per hectare. At this seeding rate, mustard sowings are maximally productive (0.77 t/ha) and are characterized by a high competitive ability to weeds. There has been proven a positive effect of nitrogen fertilizers on brown mustard productivity and growth in the number of weeds. The highest mean productivity of oilseeds for three years was obtained with the application of nitrogen doses N60 and N80 and was 0.78–0.81 t/ha (on 0.28–0.31 t/ha more than that of the control). In the same variants, dry weeds weight was the highest (105.4–106.5 g/m2 ).

Optimization of Sowing Dates and Seeding Rates with Adaptive Control of The Technology of Cultivation of Winter Barley Varieties Mavlono

One of the determining periods in the life of winter cereal plants is sowing (autumn). Only under the condition of good moisture supply and at optimal air temperature, timely and high-quality seedlings can be obtained, tillering shoots and processes of verbalization and hardening of plants to be formed. Based on the importance of the foregoing, this work presents the results of studies in bright gray-earth soils of the Kashkadarya region of the reaction of winter barley of the Mavlono variety for different periods of sowing and seed sowing rate. It was found that plant survival ranged from 86.0 to 89.9%. No significant differences in wintering of plants between crops of different sowing dates were revealed. Seeding rates did not significantly affect the height of plants, spike length and the number of grains in it, which confirms the high plasticity of winter wheat of the Mavlono variety. Our studies have shown that for winter barley of the Mavlono variety in the conditions of the Kashkadarya region, the sowing season is favorable – from 15 October to 1 November, with an optimum sowing rate of 4 million pcs / ha.

Optimization of Sowing Dates and Seeding Rates with Adaptive Control of The Technology of Cultivation of Winter Barley Varieties Mavlono

One of the determining periods in the life of winter cereal plants is sowing (autumn). Only under the condition of good moisture supply and at optimal air temperature, timely and high-quality seedlings can be obtained, tillering shoots and processes of verbalization and hardening of plants to be formed. Based on the importance of the foregoing, this work presents the results of studies in bright gray-earth soils of the Kashkadarya region of the reaction of winter barley of the Mavlono variety for different periods of sowing and seed sowing rate. It was found that plant survival ranged from 86.0 to 89.9%. No significant differences in wintering of plants between crops of different sowing dates were revealed. Seeding rates did not significantly affect the height of plants, spike length and the number of grains in it, which confirms the high plasticity of winter wheat of the Mavlono variety. Our studies have shown that for winter barley of the Mavlono variety in the conditions of the Kashkadarya region, the sowing season is favorable – from 15 October to 1 November, with an optimum sowing rate of 4 million pcs / ha.