F2 Seeds Research Articles

A CRISPR-Cas9-Derived Male Sterility System for Tomato Breeding

Male sterility can reduce cost and enable high seed purity during hybrid seed production. However, the commercial application of male sterility in hybrid seed production has not been widely used in tomatoes. CRISPR/Cas9-mediated gene editing can facilitate acceleration for the practical application of male sterility in hybrid seed production. Here, by using the CRISPR-Cas9 system, two genes DYSFUNCTIONAL TAPETUM1 (SlDYT1) and Glutathione S-transferase (SlGSTAA), which underly the two closely linked loci Male sterile 10 (Ms10) and Anthocyanin absent (AA), were knocked out simultaneously in two tomato parental lines. The generated dyt1gstaa double mutants developed green hypocotyl owing to anthocyanin deficiency and exhibited stable male sterility. Up to 92% effectiveness in selecting male sterility was achieved using green hypocotyl as a morphological marker, and thereafter an efficient and stable propagation strategy of male sterility with the aid of the morphological marker selection was developed. Furthermore, dyt1gstaa-derived hybrid seeds were produced and found to have comparable yield, weight, and germination rate with the corresponding WT-derived F1 seeds. The dyt1gstaa system not only increased hybrid seed purity to 100% but also facilitated its rapid and cost-effective determination. Moreover, this system was discovered to have no evident side effects on important agronomic traits. This study suggested that our CRISPR/Cas9-created dyt1gstaa system can be deployed in tomato hybrid seed production.

Autophagy in maternal tissues contributes to Arabidopsis seed development.

Seeds are an essential food source, providing nutrients for germination and early seedling growth. Degradation events in the seed and the mother plant accompany seed development, including autophagy, which facilitates cellular component breakdown in the lytic organelle. Autophagy influences various aspects of plant physiology, specifically nutrient availability and remobilization, suggesting its involvement in source-sink interactions. During seed development, autophagy affects nutrient remobilization from mother plants and functions in the embryo. However, it is impossible to distinguish between the contribution of autophagy in the source (i.e. the mother plant) and the sink tissue (i.e. the embryo) when using autophagy knockout (atg mutant) plants. To address this, we employed an approach to differentiate between autophagy in source and sink tissues. We investigated how autophagy in the maternal tissue affects seed development by performing reciprocal crosses between wild type and atg mutant Arabidopsis (Arabidopsis thaliana) plants. Although F1 seedlings possessed a functional autophagy mechanism, etiolated F1 plants from maternal atg mutants displayed reduced growth. This was attributed to altered protein but not lipid accumulation in the seeds, suggesting autophagy differentially regulates carbon and nitrogen remobilization. Surprisingly, F1 seeds of maternal atg mutants exhibited faster germination, resulting from altered seed coat development. Our study emphasizes the importance of examining autophagy in a tissue-specific manner, revealing valuable insights into the interplay between different tissues during seed development. It also sheds light on the tissue-specific functions of autophagy, offering potential for research into the underlying mechanisms governing seed development and crop yield.

Analysis of Genetic Variability, Correlation and Path for Yield and Its Attributing Traits in Wheat (Triticum aestivum L.)

The current study was undertaken to analyze the genetic variability, correlation and path for yield and its attributing traits at agriculture research farm, Department of Genetics and Plant Breeding, School of Agriculture, Lovely Professional University, Punjab during during Rabi 2021-22 and 2022-23. Augmented design with F2 seeds planted in ear to row fashion in 4 rows were used to study variability, correlation and path including 2 parent and its 6 F2’s for the 9 traits viz. plant height, spike length, number of tillers per plant, number of spikes per plant, number of spikelets per ear, number of grains per ear, biological yield, harvest index and grain yield. Finding revealed that grain yield revealed positive and highly significant correlation with number of tillers per plant (rp= 0.8387, rg= 0.8709) and biological yield (rp= 0.9671, rg= 0.9965) while positive and significant correlation with Number of spikes per plant (rp= 0.7168, rg= 0.7253) at both phenotypic and genotypic level. Biological yield per plant revealed highest positive direct effect (1.0642, 0.8700) with significant association with grain yield (0.9965, 0.9671) whereas Number of tillers reveals least positive direct effect on grain yield (0.0183, 0.0834) at both genotypic and phenotypic level. PCV was higher than GCV for all the traits indicated an influence of environment over the traits. Number of spikelets per ear recorded highest PCV and GCV followed by Grain yield. Heritability (h2b) found higher for grain yield (84.2) followed by Number of spikelets per ear (83.4), Number of Grains per ear (82.7) and Plant height (80.1). Genetic advance (GA) recorded higher Number of spikelets per ear (35.07) followed by Grain yield (11.93). Moderate GA recorded for Plant Height (7.67) and Biological yield (6.88) whereas Spike length (0.62) recorded lowest GA. Hence, selection for these mentioned characters could bring improvement in yield and yield components.

Partisipasi Petani dalam Kegiatan Penyuluhan dan Pelatihan Teknis Budidaya Jamur Merang di Desa Kutaampel, Kecamatan Batujaya, Karawang

Mushrooms are an alternative in meeting the need for high protein foods, but their availability is not matched by increased production. Efforts that can be made to increase the productivity of straw mushroom is to provide counseling and training to farmers about mushroom cultivation. Counseling and training on straw mushroom nurseries was given to farmers in Kutaampel Village. This paper aims to determine the participation of farmers in Kutaampel Village in counseling activities and technical training on cultivation and making seed baglogs for spreading F3 and F4 edible mushroom UNSIKA. The method used is the andragogy training method and will be held on 06 October 2022 in Kutaampel Village. The data analysis used is descriptive with reference to Arnstein's (1969) theory, namely the theory of participation which is called The Ladder of Participation theory. Based on the data analysis conducted, the level of participation of farmers in Kutaampel Village in participating in extension activities and technical training on cultivation and making baglogs for spreading F3 and F4 Unsika mushroom seeds was seen from the forms of farmer participation, namely presence, knowledge and benefits. The level of farmer participation in Kutaampel Village is at the level of the fourth rung of the consultation ladder out of a total of eight rungs of the Arnstein participation ladder (manipulation, Therapy, Informing, Consultation, Placement, Partnership, Delegated power, and Citizen control).
 Key Words: Cultivation, Participatio, Straw Mushroom

In Situ Proteomic Analysis of Herbicide-Resistant Soybean and Hybrid Seeds via Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging

Transgenic soybean is the commercial crop with the largest cultivation area worldwide. During transgenic soybean cultivation, exogenous genes may be transferred to wild relatives through gene flow, posing unpredictable ecological risks. Accordingly, an environmental risk assessment should focus on fitness changes and underlying mechanisms in hybrids between transgenic and wild soybeans (Glycine soja). Matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) was used for in situ detection and imaging of protein changes in the seeds of transgenic herbicide-resistant soybean harboring epsps and pat genes, non-transgenic soybean, wild soybean, and their F2 hybrid. Protein data clearly distinguished wild soybeans, while the F2 seeds had protein characteristics of both parents and were distinguished from wild soybean seeds. Using UPLC-Q-TOF-MS, 22 differentially expressed proteins (DEPs) were identified, including 13 specific to wild soybean. Sucrose synthase and stress response-related DEPs were differentially expressed in parental and offspring. Differences in these may underpin the greater adaptability of the latter. MSI revealed DEP distribution in transgenic, wild, and F2 seeds. Identifying DEPs related to fitness may elucidate mechanisms underlying fitness differences among the studied varieties. Our study shows that MALDI-MSI has the potential to become a visual method for transgenic soybean analysis.

Cotton heterosis and hybrid cultivar development

Cotton, the most important economic crop in the world, displays strong hybrid vigor, and has long been a subject for hybrid cultivar breeding. Here, advances in the theoretical and applied research in cotton heterosis along with its hybrid cultivar development by hand-emasculation and pollination (HEP), cytoplasmic (CMS) and genic male sterile lines (GMS) mainly in China during the past few decades are presented in this review. Three types of hybrids produced by HEP, CMS and GMS facilitating hybrid seed production with hand-pollination have been developed and are being planted simultaneously in cotton production. However, most hybrids commercially planted in production are produced by HEP, therefore, F2 seeds are being extensively planted due to the high cost to produce F1 seed. F2 generations of these combinations exceed the check cultivars in yield usually up to 5~15%. GMS genes (ms2 and ms5ms6) used in hybrid seed production and casual mitochondrial genes for G. harknessii CMS have been cloned. Challenges and opportunities in cotton heterosis and future hybrid cultivar development in cotton are discussed.

Interspecific hybridization for transfer of hull-less seed trait from Cucurbita pepo to C. moschata

Hull-less seed trait is preferred by nut and oil industries worldwide for snacking and oil extraction as it evades the expensive decorticating (dehulling) process. This seed trait is available in C. pepo only, which has small seed cavity, sensitive to various biotic and abiotic stresses, and restricted to temperate regions for cultivation. Contrarily, the related species C. moschata has wider adaptability, disease tolerance and high seed yield. Therefore, attempt was made to transfer this trait into C. moschata through conventional pollination and ovule culture using four parents of hull-less C. pepo and six of hulled C. moschata. Through conventional approach, few viable F1 seeds (12–23) were obtained by using C. pepo as female parent, but in three crosses (HLP36 × HM1343, HLP36 × HM1022 and HLP44 × HM1022) only, whereas, its use as male parent was not successful. This incompatibility issue of reciprocals was resolved through ovule culture of C. moschata genotypes HM1343 and HM6711 after 17 to 19 days of pollination with C. pepo genotypes HLP53 and HLP72, respectively. The hybridity of interspecific crosses was confirmed through SSR markers (alleles inherited from both the parents), morphological characters and micromorphological leaf traits (differed from both the parents). The successful transfer through interspecific hybridization was further established with the presence of hull-less seed in fruits of F2 populations. Outcome of this study would pave the way for enhancing the productivity and multi-season cultivation of snack-seeded pumpkin even in subtropical and tropical regions.

Combining a Mutant Allele of FAD2-1A with HD Improves the ω-6/ω-3 Ratio in Soybeans

The intake of foods with unbalanced ω-6/ω-3 ratios causes various health problems. Commodity soybeans generally have a ω-6/ω-3 ratio of 6–7:1. The recommended ratio in terms of health benefits is <4:1. This study aimed to identify the appropriate combination of mutant alleles that can reduce the ω-6/ω-3 ratio using three segregating soybean populations. F2 individuals from each population were genotyped for three different alleles of microsomal delta-12 fatty acid desaturase 2 enzyme (FAD2-1A) and an allele of homeodomain-like transcriptional regulator (HD) genes, and their five major fatty acids were assessed. F2 seeds carrying both fad2-1a and hd had slightly different ω-6/ω-3 ratios according to the different fad2-1a alleles. The fad2-1aDEL, fad2-1aS117N, and fad2-1aW293STOP alleles combined with a hd allele resulted in ω-6/ω-3 ratios with a range of 1.9–2.7:1, 2.7–3.9:1, and 2.6–3.6:1 in soybean seeds, respectively. This study revealed that the induction of mutations in FAD2-1ADEL and HD was the most efficient strategy to improve the ω-6/ω-3 ratio and elevate the ω-3 fatty acid concentrations in soybean seeds. These results provide useful information in soybean breeding programs to release a new soybean cultivar with a lower ω-6/ω-3 ratio and elevated ω-3 fatty acids, which can be a beneficial ingredient for soybean-based foods.

Genetic mapping of QTLs controlling brown seed coat traits by genome resequencing in sesame (Sesamum indicum L.).

Sesame seeds have become an irreplaceable source of edible oils and food products with rich nutrients and a unique flavor, and their metabolite contents and physiological functions vary widely across different seed coat colors. Although the quantitative trait loci (QTLs) for genetic variation in seed coat color have been extensively investigated, the identification of unique genetic loci for intermediate colors such as brown has not been reported due to their complexity. Here, we crossed the white sesame 'Yuzhi No. 8' (YZ8) and the brown sesame 'Yanzhou Erhongpi' (YZEHP) to construct a recombinant inbred line (RIL) population with consecutive self-fertilization for ten generations. The selfed F1 seeds were brown which was controlled by a dominant gene. Based on the genotyping by whole-genome resequencing of the RILs, a major-effect QTL for brown coat color was identified through both bulk segregant analysis (BSA) and genetic linkage mapping in sesame, which was located within a 1.19 Mb interval on chromosome 6 (qBSCchr6). Moreover, we found that the YZEHP seed coat initially became pigmented at 20 days post-anthesis (DPA) and was substantially colored at 30 DPA. We screened 13 possible candidate genes based on the effects of genetic variants on protein coding and predicted gene functions. Furthermore, qRT‒PCR was used to verify the expression patterns of these genes in different post-anthesis developmental periods. We noted that in comparison to YZ8 seeds, YZEHP seeds had expression of SIN_1023239 that was significantly up-regulated 2.5-, 9.41-, 6.0-, and 5.9-fold at 15, 20, 25, and 30 DPA, respectively, which was consistent with the pattern of brown seed coat pigment accumulation. This study identified the first major-effect QTL for the control of the brown seed coat trait in sesame. This finding lays the foundation for further fine mapping and cloning as well as investigating the regulatory mechanism of seed coat color in sesame.

Evaluation of Cowpea F2 Population for Resistance to Flower Bud Thrips (Megalurothrips sjostedti)

A study to screen F2 populations obtained from IT10K-837-1 x Sanzi for resistance to M. sjostedti. A total of 351 F2 plants were screened under field conditions and each line rated visually for thrips damage score, flower abortion rate, number of pods per plant and number of thrips per flower. The study was conducted during the 2020 cropping seasons where F2 seeds were planted under field conditions. Thrips damage score, flower abortion rate, number of pods per plant, and number of thrips per bloom was all visually scored for each accession. The data from the field and laboratory were analyzed using GENSTAT edition 12 to determine if there were any major variations among the cowpea genotypes. The approximate correlations among all measured parameters, including damage scores at 45 DAP, 55 DAP, 65 DAP, using were established using Breeding View software and heritability values were also calculated. There was a strong and significant correlation between thrips population and damage rating during the planting season. Thrips resistance levels identified in most genotypes in this study are interesting compared to the resistant check Sanzisabinli and can be further exploited for future studies to develop resistant varieties to improve cowpea yields.

Near-infrared spectroscopy for early selection of waxy cassava clones via seed analysis.

Cassava (Manihot esculenta Crantz) starch consists of amylopectin and amylose, with its properties determined by the proportion of these two polymers. Waxy starches contain at least 95% amylopectin. In the food industry, waxy starches are advantageous, with pastes that are more stable towards retrogradation, while high-amylose starches are used as resistant starches. This study aimed to associate near-infrared spectrophotometry (NIRS) spectra with the waxy phenotype in cassava seeds and develop an accurate classification model for indirect selection of plants. A total of 1127 F2 seeds were obtained from controlled crosses performed between 77 F1 genotypes (wild-type, Wx_). Seeds were individually identified, and spectral data were obtained via NIRS using a benchtop NIRFlex N-500 and a portable SCiO device spectrometer. Four classification models were assessed for waxy cassava genotype identification: k-nearest neighbor algorithm (KNN), C5.0 decision tree (CDT), parallel random forest (parRF), and eXtreme Gradient Boosting (XGB). Spectral data were divided between a training set (80%) and a testing set (20%). The accuracy, based on NIRFlex N-500 spectral data, ranged from 0.86 (parRF) to 0.92 (XGB). The Kappa index displayed a similar trend as the accuracy, considering the lowest value for the parRF method (0.39) and the highest value for XGB (0.71). For the SCiO device, the accuracy (0.88-0.89) was similar among the four models evaluated. However, the Kappa index was lower than that of the NIRFlex N-500, and this index ranged from 0 (parRF) to 0.16 (KNN and CDT). Therefore, despite the high accuracy these last models are incapable of correctly classifying waxy and non-waxy clones based on the SCiO device spectra. A confusion matrix was performed to demonstrate the classification model results in the testing set. For both NIRS, the models were efficient in classifying non-waxy clones, with values ranging from 96-100%. However, the NIRS differed in the potential to predict waxy genotype class. For the NIRFlex N-500, the percentage ranged from 30% (parRF) to 70% (XGB). In general, the models tended to classify waxy genotypes as non-waxy, mainly SCiO. Therefore, the use of NIRS can perform early selection of cassava seeds with a waxy phenotype.

Estimation of pollen dispersal distance in Job's tears (Coix lacryma-jobi L.) by using red leaf sheath as a morphological marker.

Job's tears (Coix lacryma-jobi L.) is grown widely in Asian countries and a crop that can fertilize with own pollen and pistils. The grains are used not only for food but also for medicinal purposes. The grain of many cultivars contains glutinous endosperm; only grains with this glutinous endosperm are suitable for use as medicine in Japan. Many wild types have non-glutinous endosperm and can easily cross with cultivar under natural environmental conditions. Because the non-glutinous endosperm trait is dominant to that of glutinous endosperm, F1 seeds produced by crosses between a cultivar and a wild type have non-glutinous endosperm. To reduce the rate of unwanted crosses, we investigated the pollen dispersal distance by using a red leaf sheath as a morphological marker. When plants were cultivated in rows 70 cm apart, the crossing rate was about 25%-35%. As the distance increased, the crossing rate decreased at a rate that could be fitted to a power approximation in fields without intervening plants and to an exponential equation in fields with intervening plants. Our data could be used as guidelines for preventing unwanted crossing with wild types when growing cultivars.

Hybridization rate and fitness of hybrids produced between the tetraploid Camelina rumelica and hexaploid Camelina sativa

Pre-release risk assessment of genetically modified (GM) Camelina sativa (L.) Crantz requires a careful evaluation of the reproductive compatibility with its closely-related Camelina species. Camelina rumelica Velen. is a naturalized weed occurring in C. sativa production region in the northwestern China. In this study, a large number of reciprocal crosses was conducted between the tetraploid C. rumelica and hexaploid C. sativa. The F1 hybrids were produced by the tetraploid C. rumelica (♀) × hexaploid C. sativa (♂) at the rate of one hybrid for 217 ovules pollinated, and one hybrid for 220 ovules pollinated in the reciprocal direction. All F1 hybrids required vernalization treatment to induce timely flowering and showed the significant lower pollen viability (< 2%) compared to the parental lines. Despite that the F1 failed to backcross with the parental lines, selfed seeds (F2) were obtained from F1 hybrids plants. The F2 hybrids showed some degree of restored pollen viability (about 20%) and successfully produced seeds by both backcrossing and self-pollination. A similar pattern was observed in the field, with F1 hybrids showing self-compatibility and reduced seed production potential. It is worthwhile to mention that all F1 and F2 plants grew well both in the greenhouse and field conditions, but with the significant lower seed production ability. A portion of selfed F2 seeds from naturally shattering persisted in the soil seedbank during summer period and subsequently germinated in late fall. By contrast, other F2 seeds may have been dormant in the soil seedbank and germinated the following spring. These altered life-cycle related traits in hybrids generates the novel ecological concerns on the persistence and population dynamics of transient hybrids in the seedbank. In summary, this study provided the evidence that the tetraploid C. rumelica and hexaploid C. sativa, which have the sympatric distributions and overlapped flowering periods, gene flow between them probably could occur. Although the rate was relatively low (about 0.5%), the introgression of life-cycle related traits into C. sativa population could alter its key life-cycle traits and raise the concerns on the soil seedbank persistence and invasiveness of transient hybrid in C. sativa production region in the northwestern China.

Haploid induction by nanobody-targeted ubiquitin-proteasome-based degradation of EYFP-tagged CENH3 in Arabidopsis thaliana.

The generation of haploid plants accelerates the crop breeding process. One of the haploidization strategies is based on the genetic manipulation of endogenous centromere-specific histone 3 (CENH3). To extend the haploidization toolbox, we tested whether targeted in vivo degradation of CENH3 protein can be harnessed to generate haploids in Arabidopsis thaliana. We show that a recombinant anti-GFP nanobody fused to either heterologous F-box (NSlmb) or SPOP/BTB ligase proteins can recognize maternally derived enhanced yellow fluorescent protein (EYFP)-tagged CENH3 in planta and make it accessible for the ubiquitin-proteasome pathway. Outcrossing of the genomic CENH3-EYFP-complemented cenh3.1 mother with plants expressing the GFP-nanobody-targeted E3 ubiquitin ligase resulted in a haploid frequency of up to 7.6% in pooled F1 seeds. EYFP-CENH3 degradation occurred independently in embryo and endosperm cells. In reciprocal crosses, no haploid induction occurred. We propose that the uniparental degradation of EYFP-fused genomic CENH3 during early embryogenesis leads to a decrease in its level at centromeres and subsequently weakens the centromeres. The male-derived wild type CENH3 containing centromere outcompetes the CENH3-EYFP depleted centromere. Consequently, maternal chromosomes undergo elimination, resulting in haploids.

Combining ability and selection of wheat populations for a tropical environment

The selection of segregating populations with the potential for derived lines is essential for breeding programs. The present work analyzes the potential of tropical F2 wheat (Triticum aestivum L.) populations originated from complete diallel cross combinations. For this purpose, eight tropical wheat cultivars were combined in a complete diallel design in 2019 after F1 seeds were multiplied in a greenhouse and the seeds of 56 F2 populations, plus the eight parents, were evaluated in the field in Viçosa, MG, Brazil in the winter harvest of 2020 using a simple lattice design (8×8). The trait scores of (1) severity of tan spot (Pyrenophora tritici-repentis), (2) severity of wheat head blast (WHB) (Magnaporthe oryzae pathotype Triticum), (3) days to heading, (4) spike height, (5) and total grain weight of the plot were evaluated. We performed a diallel analysis using mixed models to obtain the effects of general combining ability (GCA), specific combining ability (SCA), and estimation of population genotypic values. The additive effect predominated for the control of all traits, except for spike height. There were greater GCA effects for the set of parental maternal plants. Heritability, in the narrow sense, ranged from 0.20 (blast) to 0.66 (heading). There was an effect of maternal GCA for all variables, while for paternal GCA the effect was only for days passed for head and total grain weight. Populations derived from the cultivars TBIO Aton, TBIO Ponteiro, and TBIO Sossego had lower disease severity, while the combinations from BRS 254, BRS 264, and BRS 394 had earlier maturation time. The most promising combinations to derive lines for the set of traits were BRS 254 × CD 1303, BRS 394 × TBIO Aton, TBIO Aton × BRS 254, CD 1303 × BRS 254, and CD 1303 × BRS 264.

Socialization and Education on Mass Production of Liquid Organic Fertilizer with the Addition of Local Microorganism Suspension (MOL) of Bacillus cereus Strain NIGR in Pantai Cermin Village, Tanjung Pura District, Langkat Regency

In order to succeed in the development of agricultural sector in accordance with the Regulation of the Minister of Agriculture Number 67/Permentan/SM.050/12/2016 concerning Farmer Institutional Development, it is necessary to provide community service in the agricultural sector and plant cultivation as efforts to strengthen food self-sufficiency, especially during the Covid 19 pandemic. For this reason, we need to carry out community service activities for the production of liquid organic fertilizer using microorganism Bacillus cereus in Pantai Cermin Village, Tanjung Pura District. As we know Pantai Cermin Village, Tanjung Pura District, Langkat which about is 63.6 Km from Medan. In general, the majority of farmers own rice and corn areas and are members of the Gemah Ripah farmer group consisting of 30 farmers. From the results of dedication program, there are around 3000 hectares of rice and corn fields that have become a rice barn for the last 15 years, especially in Langkat Regency. Based on the results of the survey and partner interviews, several priority problems were obtained, including: a. There was a decrease in the selling price of corn in Langkat by Rp. 1,900,-/Kg from the selling price of corn in 2019 of Rp. 4,900,-/Kg to Rp. 3,000,-/Kg currently in Langkat; b. Rice farmers experienced a decrease in purchasing power of chemical compost during the Pandemic, because the price of solid organic compost from the Probiodek brand that functions as a decomposer of organic matter rose to Rp. 40,000,-/Kg; c. Farmers experienced a decline in purchasing power of chemical insecticides on the market; d. Farmers in Langkat currently do not have a knapsacksprayer and they only use 2 units of knapsacksprayer from government assistance to spray plant pests &amp; diseases and this tool is used interchangeably for all farmer groups; e. Farming management is carried out in a simple and conventional way, namely using local F1 seeds (yield) from the previous corn harvest); f. Rice harvesting as well as shelling corn use a simple method of rice mill machine. In order to develop the potential of rice and corn barns, it is necessary to strengthen the independence of farmers through community dedication program (PKM) training in the production of liquid organic fertilizer using microorganism Bacillus cereus from Ristekdikti. The focus is to develop production of liquid organic fertilizer as an alternative to chemical fertilizers and chemical insecticides. The use of microorganisms Bacillus cereus is especially useful for facilitating the decomposition of organic matter in liquid fertilizer solutions so that it is more easily absorbed by plants as fertilizer and insecticide, as well as assisting and motivating partners to continuously continue producing liquid organic fertilizers because it saves costs in purchasing chemical fertilizers and pesticides in the future so as to create economic independence for partners. This will certainly improve the economy of farmer group partners so that life can be more prosperous. All of these activities aim to foster independence in partners when the program ends. It is hoped that food self-sufficiency can be realized that is free from residues of chemical fertilizers and insecticides so that environmentally sustainable agriculture can be realized.

Screening Technique Based on Seed and Early Seedling Parameters for Cold Tolerance of Selected F2-Derived F3 Rice Genotypes under Controlled Conditions

The cold tolerance studies were carried out in a bi-parental F2 population of a cross between tolerant and susceptible parents (SKUA-529 and HEERA, respectively). The purpose was to screen the individuals of a population for primary cold-tolerance-related attributes. The information generated has a direct application and use in identifying cold tolerance quantitative trait loci (QTLs) and further can be used for genotyping with an appropriate marker system. The screening was carried out on F2-derived F3 seeds and F3 plants for seedling and agronomic traits, respectively. Two tests measuring cold tolerance were conducted. In experiment I, seeds were germinated for 28 days at 13 °C and 7 days at 28 °C, and in experiment II, the seeds were germinated for 72 h at 28 °C, 96 h at 13 °C, and once more for 72 h at 28 °C. Coleoptile length, germination percentage, and radical reduction percentages were all measured in experiment I. The radicle and coleoptile regeneration in experiment II were measured after the cold period. The improvement in cold tolerance was achieved through radicle regrowth, as evidenced by the difference between the second and first measurements. The individual lines from the F2:3 population that recorded high germination (%) were #21, #13, #14, and #15. The percentage of coleoptile length (PERCOL %) was observed to be between the ranges of 23.33% to 53.00%. The reduction in coleoptile length (REDCOL %) was also obtained, and there was less reduction in #15, #16, and #14 and it had a range between 38.46% and 75%. Radicle regrowth (REDRAG) was high at 13 °C in #7, #11, #30, #35, and #36. Survival of the seedling range was between 33.33% and up to 100%, and the highest survival rate was observed in #16. The main objective of this rotation in temperature was to emulate field conditions where there has been a drop in temperature. The evaluations were done for primary cold stress tolerance traits, and it was found that most of these traits exhibited high variability. The mapping population developed may be utilized to generate a linkage map and locate QTLs for tolerance to cold stress in rice. Further, the identified donors for cold tolerance may be utilized for breeding programs aimed at the transfer of low-temperature stress tolerance into susceptible backgrounds. In general, a genotype with improved seedling germination rates, growth rates, and leaf yellowing scores; high seedling survival; lesser reduction in coleoptile length and in radicle development; and recovery following a cold shock at the seedling stage demonstrated its cold resistance. Genotypes with a low germination percentage, a greater number of days to germination, slow growth rate and higher leaf yellowing score, high reduction in coleoptile and radicle growth, and reduced seedling survival indicated cold susceptibility.

Characteristics of Interspecific Hybridization and Inbred Progeny of Pumpkin (Cucurbita moschata Duch.) and Winter Squash (Cucurbita maxima Duch.)

Hybrid incompatibility and F1 hybrid dysgenesis in the interspecific hybridization between pumpkin (Cucurbita moschata Duch.) and winter squash (Cucurbita maxima Duch.) have been previously noted. For this reason, it is difficult to obtain F2 generations due to F1 sterility. However, back-crossing and add-crossing can be utilized to overcome these incompatibility barriers in interspecific hybridization. To date, few studies have focused on parental selection, the back-crossing process, and offspring characteristics related to interspecific hybridization. Hence, we explored the F1 seed acquisition rate, plant characteristics, and F2 generation fertility after interspecific back-crossing and add-crossing hybridization of C. moschata and C. maxima. Moreover, as a female parent, X-1 (C. moschata) yielded F1 seeds when crossed with winter squash (C. maxima) 10-04-3, 10-37, or 10-05-2. BC1F1 seeds and plants could be obtained with winter squash (C. maxima) as the recurrent parent. Some healthy F2 seeds and plants were obtained from the interspecific hybrids, including ZJ-13, ZJ-8, and ZJ-11. Further fruit nutrition quality analysis showed that the starch, polysaccharide, cellulose, and dry material contents of ZJ-7 and ZJ-8 were significantly higher than those of the parent pumpkin and winter squash lines. The bioflavonoid content of ZJ-8 was lower than that of its parents, and its soluble protein was at the median value. Meanwhile, the bioflavonoid content of ZJ-1 was lower than that of its parents, but its soluble protein was significantly higher. These results suggest that back-crossing and multi-crossing can overcome the barriers to interspecific crossing of C. moschata × C. maxima. Some interspecific hybrid fruits had nutritional contents much higher than those of their parent lines. Additionally, X-1 (C. maxima) was found to act as a bridge species in interspecific hybridization. Collectively, in this study, the barriers to interspecific hybridization of C. moschata × C. maxima were addressed through crossing methods and choice of parents, and the obtained results are expected to provide novel support for interspecific hybrid breeding between C. moschata and C. maxima.

Влияние агротехнических приемов на поражение подсолнечника болезнями на участке гибридизации и в потомстве F1 гибрида Факел

In 2019–2021, we studied influence of some agricul-tural techniques on infection of sunflower plants with pathogens of diseases on a hybridization plot and in hybrid progeny. The researches were conducted on leached black soil in the experimental –seed growing farm “Berezanskoe” (Korenovsk district, Krasnodar region). In 2020, we carried out a phytopathological estimation of disease infection of a maternal line VK 678А of a hybrid Fakel under the different agricultural techniques in the hybridization plot. In 2021, we studied sowing qualities of F1 seeds cultivated under the different agricultural techniques, and conducted the phytopathological estimation of vegetating plants of the hybrid Fakel grown at the different seed sowing rates. The purpose of the research is to reveal the effective agricultural techniques aimed on the decrease of the development of disease pathogens on sunflower on the hybridization plots to produce healthy seeds of hybrids on leached black soils of the Western Ciscaucasia as well as in F1 sowings till the economically valuable level. In whole, the studied agricultural techniques influenced positively on quality of cultivated seeds of the sunflower hybrid Fakel. We noted high meanings of the laboratory (94–98%), and field (84–87%) seeds germination in all variants. Application of a complex of fertilizers and integrated chemicals for plant protection on the hybridization plot in F1 progeny under a seed sowing rate of 60,000 pcs/ha caused a decrease of sunflower infection with downy mildew by 1,5 times, and with bacteriosis – by 8%. The biological plant protection and microfertilizers allied on the hybridization plot allow decreasing bacteriosis infection of F1 sunflower plants by 3% under the seed sowing rate of 60,000 pcs/ha, and 13% un-der 80,000 pcs/ha.

Improvement of Fruit Pubescence and Fruiting Pattern among Pure Lines and Landrace of Okra (Abelmoschus spp.) through Interspecific Hybridization

The research study was aimed at improving fruit pubescence and growth pattern in the highly mucilaginous but very spiny local and wild okra variety - ‘Ele Ogwu’ through generic hybridization with selected glabrous conventional and early maturing varieties at the Research Farm of the Department of Crop Science, University of Nigeria, Nsukka. The hybrid seeds generated from their diallel crosses were selfed to generate the F2 seeds. Backcrosses (BC1 and BC2) were also made to the much improved and glabrous varieties. The parents, F1, F2 and BC genotypes were sown in an experimental field in a randomized complete block design and organoleptic assessment was done at harvest. The F2 hybrids from the crosses, ‘UHIE x CLM’ and ‘AGW x CLM’, yielded some smooth fruits; although most of the hybrids generated, exhibited intermediate smoothness, except for ‘OGW x UHIE’ and ‘OGW x LD88’ that exhibited high degree of spineness. Most of the F2 hybrids generated exhibited intermediate growth and fruiting pattern, except for ‘OGW x UHIE’ which showed indeterminate pattern. The Chi-square statistics for the F2 showed that fruit pubescence for the highly spiny landrace and the more glabrous improved ones was monogenically controlled with incomplete dominance, while growth pattern were polygenically controlled. The successful backcrosses obtained showed reduction in the proportion of fruits spininess and increased fruit determinate growth pattern. This hereby indicates the prospect of obtaining okra plants with glabrous, highly appealing and determinate growth pattern with early maturity from the local, wild spiny but mucilaginous, nutritious and high yielding local varieties through sustained hybridization programme.