Solar energy components in cotton and safflower crops

Solar energy components at different phenophases of cotton (Gossypium hirsutum) and safflower (Carthanus tinctorius) crops were measured. The percentage of different components are calculated. Solar energy utilisation component is found maximum during flowering stage in cotton and during seed setting stage in safflower. The albedo is constant till the flowering stage and gradually increases reaching a maximum at the boll development stage and later decreases gradually in the cotton crop. In the case of safflower, the albedo gra dually increases till the seed setting stage is attained and decreases. The transmitted component first decreases and then increases in both the crops.

The Effect of Titanium Organic Complex on Pollination Process and Fruit Development of Apple cv. Topaz

Optimal weather conditions are necessary for the proper course of the flowering process and high activity of pollinators, which is the most important factor affecting pollination. Because weather conditions do not always favour effective pollination and because pollinators’ activities are decreasing, the application of compound stimulating pollination and fertilization may be a good perspective for increasing yield. Titanium is considered a beneficial element for plants. Preliminary studies have indicated the positive effect of titanium organic complex on pollen adhesion to the stigma and pollen germination on the stigma of tomato and cucumber. Therefore, a 2-year experiment was designed to determine the effect of titanium organic complex application on the pollination process and fruit development of apple cv. Topaz (Malus domestica Borkh.) The experiment demonstrated the positive effect of titanium organic complex on fertilization of ovules because of effective pollination, seed setting, and fruit development of apple. Application of titanium organic complex improved pollen adhesion to the stigma and pollen germination on the stigma. In addition, titanium organic complex increased the number of pollen tubes growing through the pistil style, which resulted in fertilization that was more effective, as confirmed by the higher number of seeds set in fruits. Higher numbers of seeds set in fruits positively affected their weight and size. Therefore, fruit harvested from trees to which titanium organic complex was applied were characterized by greater weight, length, and diameter compared to fruits obtained from the trees to which titanium organic complex was not applied.

Automatic and Accurate Calculation of Rice Seed Setting Rate Based on Image Segmentation and Deep Learning

The rice seed setting rate (RSSR) is an important component in calculating rice yields and a key phenotype for its genetic analysis. Automatic calculations of RSSR through computer vision technology have great significance for rice yield predictions. The basic premise for calculating RSSR is having an accurate and high throughput identification of rice grains. In this study, we propose a method based on image segmentation and deep learning to automatically identify rice grains and calculate RSSR. By collecting information on the rice panicle, our proposed image automatic segmentation method can detect the full grain and empty grain, after which the RSSR can be calculated by our proposed rice seed setting rate optimization algorithm (RSSROA). Finally, the proposed method was used to predict the RSSR during which process, the average identification accuracy reached 99.43%. This method has therefore been proven as an effective, non-invasive method for high throughput identification and calculation of RSSR. It is also applicable to soybean yields, as well as wheat and other crops with similar characteristics.

The influence of abiotic stress on the crop and seed setting

The potential productivity of an ear by the time of flowering is predetermined by the number of fertile flowers and the “planned” mass of 1000 grains - through the number of flowers with which the grain size is inversely correlated, by the resources of the shoot vegetative mass and by the possibility of realizing these resources. The influence of pinching and incomplete setting of seeds in the conditions of dry growing seasons of 2018 and 2020 for the formation of grain is considered. It was concluded that grains from the first three flowers have a predominant contribution to the productivity of a spikelet. The naked oat variety Nemchinovskiy 61 could not realize its biological potential due to abiotic stresses. Due to the incomplete seed setting, an average of 2.03 grains out of 5-6 flowers were preserved for harvesting. Reduction of flowers number in a spikelet in naked oats to two as the direction in breeding has no prospects. To increase the adaptability of naked oats to abiotic stresses, parental forms with a relatively small number of grains in a spike, which are capable to utilize precipitation, should be involved in hybridization, to increase the mass of 1000 grains.

Screening of Pearl Millet Genotypes for High Temperature and Drought Tolerance Based on Morpho-Physiological Characters

Aims: Screening of pearl millet genotypes lines for high temperature and drought tolerance. Study Design: Randomized Block Design (RBD) with three replications. Place and Duration of Study: ICAR-AICRP on Pearl Millet, Mandor during summer 2017-18. Methodology: Fifteen genotypes (J-2290, J-2340, J-2479, J-2500, J-2503, J-2507, J-2517, J-2534, JMSB-9904, JMSB-101, JMSB-20064, JMSB-20102, JMSB-20071, JMSB-20082 and JMSB-20091) of pearl millet received from Main Pearl millet Research Station, Junagadh Agricultural University, Jamnagar were evaluated during summer season of 2017-18 at research Farm of ACIRP on pearl millet, Mandor, Agricultural University, Jodhpur under terminal moisture stress and irrigated conditions in two sets of randomized block design with three replications. Grain yield, stover yield, Relative Water Content (RWC), harvest index, threshing percentage and chlorophyll content were recorded. Results: The suitability of the genotypes was judged in terms of grain yield, stover yield, RWC, harvest index, threshing percentage and chlorophyll content. The results showed that due to the terminal stress, the mean performance of all yield attributing characters including grain yield and chlorophyll, RWC and seed setting was reduced. The inbreds J-2479, J-2503 and J-2507 were high yielders due to high seed setting percentage under terminal stress conditions. Conclusion: The lines viz., J-2479, J-2503 and J-2507 can be used for further breeding programme to develop varieties suitable under high temperature and low moisture conditions.

The transcription factor CmLEC1 positively regulates the seed-setting rate in hybridization breeding of chrysanthemum

Distant hybridization is widely used to develop crop cultivars, whereas the hybridization process of embryo abortion often severely reduces the sought-after breeding effect. The LEAFY COTYLEDON1 (LEC1) gene has been extensively investigated as a central regulator of seed development, but it is far less studied in crop hybridization breeding. Here we investigated the function and regulation mechanism of CmLEC1 from Chrysanthemum morifolium during its seed development in chrysanthemum hybridization. CmLEC1 encodes a nucleic protein and is specifically expressed in embryos. CmLEC1’s overexpression significantly promoted the seed-setting rate of the cross, while the rate was significantly decreased in the amiR-CmLEC1 transgenic chrysanthemum. The RNA-Seq analysis of the developing hybrid embryos revealed that regulatory genes involved in seed development, namely, CmLEA (late embryogenesis abundant protein), CmOLE (oleosin), CmSSP (seed storage protein), and CmEM (embryonic protein), were upregulated in the OE (overexpressing) lines but downregulated in the amiR lines vs. wild-type lines. Future analysis demonstrated that CmLEC1 directly activated CmLEA expression and interacted with CmC3H, and this CmLEC1–CmC3H interaction could enhance the transactivation ability of CmLEC1 for the expression of CmLEA. Further, CmLEC1 was able to induce several other key genes related to embryo development. Taken together, our results show that CmLEC1 plays a positive role in the hybrid embryo development of chrysanthemum plants, which might involve activating CmLEA’s expression and interacting with CmC3H. This may be a new pathway in the LEC1 regulatory network to promote seed development, one perhaps leading to a novel strategy to not only overcome embryo abortion during crop breeding but also increase the seed yield.

Identification of QTLs for Heat Tolerance at Flowering Stage Using Chromosome Segment Substitution Lines in Rice

High temperature is a major stress in rice production. Although considerable progresses have been made on investigating heat tolerance (HT) in rice, the genetic basis of HT at heading stage remains largely unknown. In this study, a novel set of chromosome segment substitution lines (CSSLs) consisting of 113 lines derived from a heat-resistant indica variety N22 and a heat-sensitive indica variety 9311 was developed and used for the analysis of genetic basis of HT. The heat sensitivity index (HSI) calculated based on seed-setting rates under natural and high temperature environments was used to evaluate the influence of HT at rice heading stage. Totally, five QTLs associated with HT were detected based on seed-setting rate (SSR) evaluation; these were named qSSR6-1, qSSR7-1, qSSR8-1, qSSR9-1 and qSSR11-1 located on chromosomes 6, 7, 8, 9 and 11, respectively. Heat-tolerant alleles of the QTLs were all derived from N22. Among them, qSSR9-1 overlapped with QTLs identified previously, while the remaining QTLs were found novel. Especially, qSSR7-1 explained a high phenotypic variation of 26.35% with a LOD score of 10.75, thus deserved to be further validated. These findings will increase our understanding of the genetic mechanism underlying HT and facilitate the breeding of heat-tolerant rice varieties.

Pollen plant analysis of different sunflower genotypes

Pollen analysis makes it possible to determine the reproductive potential of sunflower plants by the morphological characteristics of pollen grains with the aim of breeding to increase yields. The research was carried out in 2019–2020 at V.S. Pustovoit All-Russian Research Institute of Oil Crops, Krasnodar. The objects of the research were plants of cultivated sunflower Helianthus annuus L.: four hybrids – Factor, Typhoon, Oxy and NK Brio, confectionery variety Djinn, two parental lines of the hybrid Oxy – VK876 B and VK195, as well as a perennial wild growing hexaploid species H. tuberosus L. Pollen was stained with acetoorcein and viewed under a microscope Micros MS 20. The diameter of pollen grains in the hybrids Factor, NK Brio, Typhoon, Oxy, the line VK195 and the cultivar Djinn varied from 34 to 31 μm. The line VK876 B and H. tuberosus were characterized by the lowest values of this trait – 29 and 27 μm, respectively. For the line VK876 B and the hybrid Oxy, significant morphological heterogeneity of pollen was observed, which was expressed in a correspondingly high proportion of abnormal pollen grains – 34 and 26%. At the same time, there was a two-peak distribution of the values of the diameter of pollen grains. The morphological heterogeneity of the pollen grains of the hybrid Oxy is associated with the dominant inheritance of this trait from the maternal CMS-form VK876 A, since the paternal line VK195 has a normal characteristic of pollen grains. The pollen of the hybrid NK Brio showed a significantly higher (by 25%) seed setting in crossing with the CMS tester than that of the hybrid Oxy, which confirms the assumption that there is a relation between an increased proportion of abnormal pollen grains and reduced pollen fertility.