Oat samples valuable for breeding in the forest steppe of the Ob region with the optimal combination of yield elements

The results of the study of collection oat samples of various ecological and geographical origin are presented. The experiments were carried out in Novosibirsk region in 1994-2018. The sources that combine the optimal density of the productive plant stand and the mass of grain from the panicle were identified according to the ripeness groups. There were 413 collection samples of spring oats studied from 42 countries of the world for 25 years. Collection varieties were evaluated in nurseries of the 2nd-3d year of study. To identify the best samples, a scoring evaluation system of the traits under consideration, i.e. the density of the productive plant stand and the mass of grain from the panicle, was used. Comparison of genotypes for these traits was carried out within a group of varieties with an equal score for the duration of the seedlings -wax ripeness period. The standard varieties Krasnoobsky and Rovesnik were studied for all 25 years, therefore, all years were divided into three groups according to the average biological yield of these varieties. The first group includes 5 years, in which the standard varieties formed a low yield - less than 300 g/m2. The second group includes 14 years with a standard yield of 300-600 g/m2. The third group includes 5 years with the most favorable conditions for the formation of a high biological yield - more than 600 g/m2. A significant correlation between biological productivity and panicle productivity was noted in the standard variety Krasnoobsky during the years with a medium yield and in the standard variety Rovesnik during the years with a high yield. With the traits being evaluated in points, biological productivity showed a strong positive correlation with panicle productivity in Krasnoobsky variety in all groups of years, and in Rovesnik variety only in groups of years with medium and high yield. The sources of biological productivity of oats were identified by ripeness groups: very early - VIR-14522 (Dukat, Poland); early-ripening - VIR-14223 (Ardo KR-FPTS, Czechoslovakia); mid-early - VIR-15340 (Uran, Omsk region), VIR-14729 (SG-K-93682, the Czech Republic), VIR-14588 (Gramena, Germany), VIR-14582 (Carl Theodor, Germany), VIR-15012 (Togurchanin, Tomsk region), VIR-14706 (Keeper, Great Britain), VIR-14581 (Borka, Germany), VIR-15178 (Begunok, Ulyanovsk region) and Novosibirsky 5 (Novosibirsk region); mid-ripening - VIR-14377 (Mutika 572, Omsk region), VIR-14520 (Kwant, Poland), VIR-15254 (AC Mustang, Canada), VIR-15280 (55h 2106, Moscow region) and VIR-14527 (OM 1385, Great Britain); medium-late - VIR-15065 (Irtysh 22, Omsk region), VIR-14860 (Malysh, Tyumen region) and VIR-15103 (R8N9 3037-3072, Krasnoyarsk region).

High insect pest damage increases faba bean (Vicia faba) yield components but only in the absence of insect pollination

Identifying and quantifying crop stressors interactions in agroecosystems is necessary to guide sustainable crop management strategies. Over the last 50 years, faba bean cropping area has been declining, partly due to yield instabilities associated to uneven insect pollination and herbivory. Yet, interactions between pollinators and a key pest, Bruchus rufimanus (florivorous and seed predating herbivore), on faba bean yield have not been investigated. Using a factorial cage experiment in the field we investigated how interactions between two potential stressors, lack of pollination from Bombus terrestris and herbivory by B. rufimanus, affect faba bean yield. Lack of insect pollination reduced bean weight per plant by 15%. Effects of B. rufimanus herbivory differed between the individual plant and the plant-stand scale (i.e. when averaging individual plant scale responses), likely due to high variation in the level of herbivory among individual plants. At the individual plant scale, B. rufimanus herbivory increased yield but only in the absence of pollinators, possibly due to plant over-compensation and/or pollination by B. rufimanus. At the plant-stand scale, we found no effect of B. rufimanus on yield. However, there was a tendency for heavier individual bean weight with insect pollination, but only when B. rufimanus herbivory was absent, possibly due to a negative effect of B. rufimanus on the proportion of legitimate flower visits by B. terrestris. This is the first experimental evidence of interactive effects of B. terrestris and B. rufimanus on faba bean yield. Our preliminary findings of negative and indirect associations between B. rufimanus and individual bean weight call for a better acknowledgment of these interactions in the field in order to understand drivers of crop yield variability in faba bean. This study showed that herbivory can increase yield, but this effect is only detectable when investigated in combination with lack of pollination.

Rice- Fallows: A Destiny or Opportunity to Farmers from Bhagalpur District of Bihar

The study attempted to critically review the status and scope of rice fallows in India, specifically to the Bhagalpur district of Bihar. Technological progress and capital-intensive cultivation through conversion of marginal lands into mitigated the ever-increasing demand of food production for burgeoning population to some extent but a continuous expansion of fallow lands brought serious concern on policy dynamics. The changes in temporal and spatial distribution of fallow lands are mostly documented due to increasing variability in the precipitation and irrigation water, and low level of mechanization. However, this is not true in case of flood and drought prone areas, and state like Bihar, where farmers are financially weak and technological expansion is very limited. The results revealed that, the most important constraint for rice fallows was rainfed ecology, low soil moisture content after the harvest of paddy and lack of irrigation facilities. The farmers also identified lack of short duration and high yielding varieties, poor plant stand, no use of fertilizers and chemicals and severe weed infestation in the field as the other major constraints. The size of land holding was found positively significant with rice fallows area indicating that the income penalty of keeping land fallow could not be tolerated by marginal small farmers

Performance of micro-nutrients on growth and yield attributes of linseed (Linum usitatissimum L.) under limited irrigation

A field experiment was conducted during Rabi season of 2019-20 at Oil Seed Research Farm of C S Azad University of Agriculture and Technology, Kanpur. The experiment consisted 9 treatments viz. T1: Control, T2: Soil application of ZnSO4 @ 25 kg ha-1, T3: Foliar application of ZnSO4 @0.5% at 45 DAS, T4: Soil Application of ZnSO4 @ 25 kg ha-1 + Foliar application of ZnSO4 @0.5% at 45 DAS, T5: Soil application Borax @ 1.5 kg ha-1, T6: Foliar application of Borax @ 0.3 % at 45 DAS, T7: Soil application of Borax @ 1.5 kg ha-1 Foliar application of Borax @ 0.3 % at 45 DAS, T8: Foliar application of ZnSO4 @ 0.5% + Borax @ 0.3% at 45 DAS and T9: Soil application of ZnSO4 @ 25 kg ha-1 + Borax @ 1.5 kg ha-1 in soil assigned in Randomized Block Design with three replication. The Linseed cv Shekhar was used in the experiment. The results in significantly maximum plant stand, plant height, yield attributes: Days to 50% flowering and maturity, Number of capsules plant-1 and number of seeds capsule-1, 1000-seed weight (g) was significantly affected by T9 and T8 treatments. The highest 1000-seed weight (8.97) under (T9) treatment were soil application of ZnSO4 @ 25 kg ha-1 + Borax @ 1.5 kg ha-1 at the time of sowing as compared to all the treatments except treatment No.(T8 ) Foliar application of ZnSO4 @ 0.5% + Borax @ 0.3% at 45 DAS under limited irrigation of central Uttar Pradesh.

Phytophthora sojae pathotype distribution and fungicide sensitivity in Michigan

Identifying the pathotype structure of a Phytophthora sojae population is crucial for the effective management of Phytophthora stem and root rot of soybean (PRR). P. sojae has been successfully managed with major resistance genes, partial resistance, and fungicide seed treatments. However, prolonged use of resistance genes or fungicides can cause pathogen populations to adapt over time, rendering resistance genes or fungicides ineffective. A statewide survey was conducted to characterize the current pathotype structure and fungicide sensitivity of P. sojae within Michigan. Soil samples were collected from 69 fields with a history of PRR and fields having consistent plant stand establishment issues. Eighty-three isolates of P. sojae were obtained, and hypocotyl inoculations were performed on 14 differential soybean cultivars, all of which carry a single Rps gene or no resistance gene. The survey identified a loss of effectiveness of Rps genes 1b, 1k, 3b and 6, compared to a previous survey conducted in Michigan from 1993-1997. Three effective resistance genes were identified for P. sojae management in Michigan; Rps 3a, 3c, and 4. Additionally, the effective concentration of common seed treatment fungicides to inhibit mycelial growth by 50% (EC50) was determined. No P. sojae isolates were insensitive to the tested chemistries with mean EC50 values of 2.60x10-2 µg/ml for ethaboxam, 3.03x10-2 µg/ml for mefenoxam, 2.88x10-4 µg/ml for oxathiapiprolin, and 5.08x10-2 µg/ml for pyraclostrobin. Results suggest that while there has been a significant shift in Rps gene effectiveness, seed treatments are still effective for early season management of this disease.

Maize-soybean intercrop silage yield and quality with different nitrogen levels and plant population

This study hypothesizes that maize-soybean intercrop with lower maize plant population and nitrogen levels can allow better soybean development and yield, which may offset lower maize biomass and silage crude protein yield. Experiment was carried out in a randomized complete block design arranged in a 2 x 5 factorial scheme, with three replications. Treatments consisted of two different maize-soybean plant stand (40,000 and 60,000 plants ha-1) and five nitrogen fertilization levels (0, 50, 100, 150, and 200 kg ha-1). As a result, soybean biomass yield increased at the lower maize plant stand, although, maize and total (maize + soybean) biomass yield were higher at the greater maize plant stand. Thus, individual maize plants and total dry matter yield increased as nitrogen levels were increased. However, there was no effect of the studied factors on the silage crude protein yield per area, indicating a great potential of soybean to offset biomass yield reduction trough silage quality improvement. Moreover, since there was no difference on total silage crude protein yield per hectare, it is suggested that the adoption of maize-soybean intercrop with lower maize plant stand (40 thousand maize plants ha-1) and with lower nitrogen values is a more environmentally friendly approach to increase farmland sustainability while decreasing environmental and productivity costs. Intermediate levels may be evaluated in future studies

Vigor de sementes de cenoura recobertas com bioestimulante de Solieria filiformis

To guarantee seeds with high physiological quality performing in a uniform, resilient and tolerant to abiotic stress plant stand, procedures that can improve the potential of the processed seed. Biostimulants are considered promising alternatives, both to improve the physiological performance of plants and in resilience and stress tolerance. The objective of this study was to verify the effect of coatingseeds of different cultivars of carrots with biostimulant based on algae Solieria filiformison seed germination and seedling development under thermal stress. The experiment was conducted in a completely randomized design, with a 3 x 4 factorial scheme (temperaturesand doses), with five replications. Carrot seeds from the cultivars Brasília, Danvers, Esplanada and Planalto were used, and the seeds were coated with doses of 0, 2, 4 and 8 mL.L-1 of biostimulant. After covering, the seeds were submitted to the following: percentage and speed of germination, length of seedlings and dry mass of seedlings. The results obtainedwere found in the analysis of variation and in the analysis of regression (doses) and Tukey's test (moderate). The analysis and interpretation of the results obtained in the present study allowed to conclude the high thermal stress, for all varieties, at a temperature of 35 ° C, to reduce the reduction of the analyzed variables. Furthermore, the covering of carrot seeds with the biostimulant of Solieria filiformis, in general, does not promote improvements in seed germination and in the development of carrot seedlings under thermal stress (35 °C); however, we present beneficial results for the variables analyzed at 20 and 30 ° C.

Amaranth irrigation frequency in northeast Patagonia, Argentina

Introduction. The production potential of grain amaranth has recently been demonstrated in northeastern Patagonia, Argentina. This crop under irrigation and in a temperate semi-arid climate showed an adequate development of the plants in their different phenological stages with high economic performance. Objectives. This study explored the response of Amaranthus cruentus cv Mexicano to different irrigation frequencies in the lower valley of Río Negro river, Patagonia, Argentina. Method. The experimental design was of three blocks with randomized treatments (subplots), each one corresponding to a different irrigation frequency. The first six irrigations were performed every 7 days for all the treatments, to ensure the establishment of the crop. Then the following treatments were applied: irrigation every 7 days (FI), every 14 days (FII), and every 21 days (FIII). The following biometric variables and their components were measured: height of plant, number of leaves, biomass and economic yield. Results. The results suggest that the optimum irrigation frequency was FII (14 days), resulting in an adequate plant stand at panicle initiation and allows a proper development of plant with optimal biological and economical yields and the highest efficiency of water use (4.02 kg·m-3). Conclusions. The contributions of this study demonstrated the production potential of A. cruentus crop in the lower valley of the Río Negro river under irrigation, representing the southernmost study on irrigation frequency made for this grain crop in the world. A management of irrigation water of 7 days for the establishment of the crop and then with a frequency of 14 days showed the highest yield and the best water use efficiency.

Refrigerated storage period of Rhizophores for Yacon propagation

Yacon, is known for its tuberous roots, which are consumed as functional food and is propagated mostly in the vegetative form, via propagules, so-called rhizophores. However, they are organs with little durability in its propagation form. Storing them in cold chamber conditions, can be a viable alternative for the seedlings production of the culture. The objective of this study was to verify the influence of the refrigerated storage period of yacon rhizophores in the initial plant development. The experimental design was completely randomized with eight replicates and six treatments and the rhizophores were place in the refrigerated storage for: 7, 14, 21, 28 and 35 days; and time zero (planting without storage). The results show that the rhizophores in the refrigerated storage in a temperature of 8 to 10°C, for a period between 21 to 35 days had better sprouting rate (speed and vigor), reducing mortality, which favored the initial yacon growth. The refrigerated storage between 21 and 35 days showed to be an alternative that resulted in a uniform plant stand in crops, also reflecting the uniformity in the harvest, and minimizes the problem of seasonality offering culture propagation material.