Effect of potassium and boron spraying in yield and quality characteristics for sunflower crop Helianthus annuus L. var luleo

"A field experiment was carried out during the autumn season of 2016 in one of the Agricultural fields in the area of Abu- Guelana ,which is 13 km from the center of Muthanna province , To find out the effect of potassium and boron spraying in the yield and quality characteristics , for sunflower crop - variety Luleo.Used in this study completely randomized block design Arrangement factorial experiment , The study included two factors : The first factors of four concentrations of potassium spray (0, 2500, 5000, 7500) mg K L-1 , and the second factor four concentrations of boron spray (0, 50, 100, 150) mg B L-1 . The mean of the treatments was compared with the least significant difference (L.S.D) at a probability level of 0.05% . Results showed that the potassium spray treatment 7500 mg k L-1 was significantly higher in all studied traits ,(number of seeds/head , weight of thousand seed , fertility percentage ,seed yield , total seed yield and total oil yield) , The results showed that the treatment of boron spray with 100 mg B L-1 concentration was significantly higher in all studied traits. The overlap treatment showed significant superiority in all the traits"

Global Identification of ANTH Genes Involved in Rice Pollen Germination and Functional Characterization of a Key Member, OsANTH3

Pollen in angiosperms plays a critical role in double fertilization by germinating and elongating pollen tubes rapidly in one direction to deliver sperm. In this process, the secretory vesicles deliver cell wall and plasma membrane materials, and excessive materials are sequestered via endocytosis. However, endocytosis in plants is poorly understood. AP180 N-terminal homology (ANTH) domain-containing proteins function as adaptive regulators for clathrin-mediated endocytosis in eukaryotic systems. Here, we identified 17 ANTH domain-containing proteins from rice based on a genome-wide investigation. Motif and phylogenomic analyses revealed seven asparagine-proline-phenylalanine (NPF)-rich and 10 NPF-less subgroups of these proteins, as well as various clathrin-mediated endocytosis-related motifs in their C-terminals. To investigate their roles in pollen germination, we performed meta-expression analysis of all genes encoding ANTH domain-containing proteins in Oryza sativa (OsANTH genes) in anatomical samples, including pollen, and identified five mature pollen-preferred OsANTH genes. The subcellular localization of four OsANTH proteins that were preferentially expressed in mature pollen can be consistent with their role in endocytosis in the plasma membrane. Of them, OsANTH3 represented the highest expression in mature pollen. Functional characterization of OsANTH3 using T-DNA insertional knockout and gene-edited mutants revealed that a mutation in OsANTH3 decreased seed fertility by reducing the pollen germination percentage in rice. Thus, our study suggests OsANTH3-mediated endocytosis is important for rice pollen germination.

Microevolutionary relationships between biotypes of Elymus confusus, E. peschkovae, and E. sibiricus (Poaceae) according to hybridization and sequencing of the nuclear gene GBSS1 (waxy)

According to descriptions, the Siberian species E. peschkovae and E. confusus differ in the presence or absence of trichomes on lemma and rachilla surfaces only. Two methods were used for study microevolutionary relationships between these species: hybridization of biotypes from different locations and analysis of nucleotide sequences of the low-copy nuclear gene GBSS1. Created and grown hybrids in combinations AMU-8804 × BER-0807 and AMU-8804 × BUK-1109 showed complete seed sterility in two field vegetations. Taking into account wide species areas, 3 hybrids were created between Magadan biotypes from a common habitat in the combination E. confusus MOL1887 × E. peschkovae MOL-1882. The plants showed seed fertility (SF) of 0–3 %. This result does not obscure the possibility to assess SF in the F2 generation and the character of inheritance of diagnostic traits. A comparative study of the GBSS1 gene sequences in accessions was carried out in comparison with clones of reference species. Differentiation of clones by the St2 subgenome in E. confusus, E. peschkovae, E. sibiricus and E. caninus did not reveal a clear relationships between the species. Meanwhile, a certain species specificity for the H1 subgenome was noted, confirming the existence of microevolutionary isolation of these species.

Comparative Studies on Mutagenic Effectiveness and Efficiency in Horsegram [Macrotyloma uniflorum (Lam) Verdc.]

Background: Two horsegram varieties viz., PAIYUR 2 and CRIDA1-18R were mutated with gamma rays (G), electron beam (EB), G+EB and G+EMS (ethyl methane sulphonate) to determine the mutagenic potency in breeding programme.Methods: Uniform seeds treated with different mutagenic doses were raised in randomized block design which constituted M1 generation. Each plant was harvested individually and forwarded to M2 generation following plant to progeny row method.Result: A dose dependant decline was observed for seed germination, plant survival, root length, shoot length, plant height, pollen fertility and seed fertility in M1 population. Wide spectrum of chlorophyll mutants was induced in M2 generation with maximum frequency at EB followed by combination treatments (G+EMS and G+EB) in both varieties. The mutagenic effectiveness ranged from 0.14 per cent to 1.45 per cent in PAIYUR 2 and 0.15 per cent to 1.71 per cent in CRIDA1-18R. The high mutation rate for effectiveness was exhibited by G and G+EB. With reference to sterility, EB was found to be efficient mutagen in both varieties whereas varied efficiency was noted for lethality (EB - PAIYUR 2; G+EMS - CRIDA1-18R) and injury (G - PAIYUR 2; G+EMS - CRIDA1-18R).

Flowering sex ratios and costs of reproduction in gynodioecious Ocotea oblonga (Lauraceae)

In gynodioecious plant species, both female and hermaphrodite individuals produce fruit, but only hermaphrodites produce pollen. Such sex-specific differences in reproductive investment may contribute to dimorphism, but the magnitude and ecological effects are still unclear, especially for gynodioecious tropical trees where collecting flowers and determining the sex is complex. We documented flowering and fruiting over three years in a natural population of Ocotea oblonga (Lauraceae) trees in a tropical moist forest, Panama. We determined sex from freshly collected flowers, counted and measured fruit, and used long-term growth data for each individual. We confirmed that O. oblonga is gynodioecious. No tree switched sex or had flowers of both sexes. The population was hermaphrodite-biased. We found no ecological differences in reproductive investment (seed, fruit, or tree size, or growth rate) between the sexes, indicating that the sex differential in the cost of reproduction is much smaller in woody gynodioecious taxa than in dioecious taxa. Females produced more fruit than hermaphrodites, which may contribute to their persistence in the population. Accordingly, and contrary to most studies of temperate gynodioecious populations, our study of a tropical tree shows no differential cost of reproduction in a hermaphrodite-biased population. Consequently, other factors such as seed fertility or herbivory could drive the biased sex ratio in this population.

A sexual hybrid and autopolyploids detected in seed from crosses between Neslia paniculata and Camelina sativa (Brassicaceae)

It is important to understand the probability of hybridization and potential for introgression of transgenic crop alleles into wild populations as part of pre-release risk assessment. Here we completed bidirectional crosses between the emerging crop, camelina [Camelina sativa (L.) Crantz] and its weedy relative, ball mustard [Neslia paniculata (L.) Desv.]. Ball mustard is a self-compatible annual that produces hard ball-like seeds similar to canola or mustard seed in size and shape. A total of 1593 crosses were completed and collected with camelina as the maternal parent, while 3253 crosses were successfully collected in the reverse direction. Putatively hybrid seedlings were screened with flow cytometry and species-specific nuclear ribosomal internal transcribed spacer (ITS) markers. Three plants had DNA contents close to expectations for hybrids, but only one of these, formed on camelina, had the expected ITS markers. This hybrid exhibited low fertility, and neither self-pollination nor backcrossing produced viable progeny. The other two plants, formed on ball mustard, had high pollen and seed fertility and were identified as ball mustard neoautotetraploids. Therefore, the hybridization rate between camelina and ball mustard is relatively low at one in 20 000 ovules pollinated when camelina is the maternal parent. However, autotetraploids may form frequently in ball mustard, and tetraploid populations may exist in nature.

Semidwarf Gene d60 Affected by Ubiquitous Gamete Lethal Gene gal Produced Rare Double Dwarf with d30 via Recombination Breaking Repulsion-Phase Linkage on Rice Chromosome 2

The genotype of gal and d60 were investigated in 33 rice varieties chosen from representative semidwarf and dwarf rice varieties. These were crossed with three tester lines, the d60Gal line (genotype d60d60GalGal), the D60gal line (Koshihikari, D60D60galgal), and the D60Gal line (D60D60GalGal). Each F1 plant was measured for culm length, and seed fertility. As a result, all F1 lines with the d60Gal line showed tallness and partial sterility, reduced by 25% in average from those with the D60gal line (Koshihikari) and the D60Gal line. These data indicated that the genotype of the 33 varieties is D60D60galgal and that the d60 locus is not allelic to those of sd1, d1, d2, d6, d18k, d29, d30, d35, d49, d50, and qCL1 involved in the 33 varieties. In addition, the gal gene is not complementarily activated with the semidwarf and dwarf genes described above, other than d60. The Gal gene will be ubiquitously distributed in rice. It is emphasized that Gal is a rare and valuable mutant gene essential to the transmission of d60. The double dwarf genotype of homozygous d30d60 was rarely gained in the F3 of the d30 line × d60 line by breaking their repulsion d60-D30 linkage on chromosome 2.

The effect of pollen performance on low seed fertility in a Greek population of Juniperus excelsa

The Juniperus excelsa (Cupressaceae) forest in northern Greece has been facing a documented severe decline of natural regeneration over the last few years. In order to dissect the physiological components of the low regeneration, pollen originated from different sites as well as from trees of different height was investigated in terms of viability and in vitro germination capacity. In addition, embryo development and viability of the first year immature seeds were further assessed. Pollen was found to present high viability (61.5–93.2%) in all sites and tree height classes. However, pollen germination was quite low (maximum germination percentage recorded was 30.2%). The low pollen germination capacity recorded in trees above 6 m in height was reflected in the subsequent low percentages of successful embryo development and viability found in the produced seeds. These results suggest that low seed fertility in Juniperus excelsa is associated with reduced pollen germination, suggesting a complex regeneration mechanism and is considered an additional step in shedding light on the physiological basis of the low natural regeneration of Juniperus excelsa.

Adaptation to ex vitro conditions of Stevia rebaudiana (Bertoni) Hemsl. regenerants

Stevia rebaudiana (Bertoni) Hemsl. belongs to Asteraceae family and is of great importance for pharmaceutical and food industries. Stevioside obtained from the leaves of this plant is regarded as a valuable natural sweetener. Low seed fertility is one of the most important problems in stevia production. It multiplies almost exclusively in a vegetative way. Plant tissue culture is an efficient method for mass propagation of S. rebaudiana. We studied the effect of various concentrations of auxins on rooting stevia shoot cuttings under in vitro conditions. We found that adding 0.6-1.0 mg l-1 IBA or 0.2 mg l-1 IAA to the В5 medium is effective forrooting the shoot fragments of this species. The regenerants were adapted to ex vitro conditions for 3 weeks on a hydroponic setup filled with a solution of mineral salts according to the quarter-strength Murashige and Skoog (MS) basal medium modified by the content of KH2PO4 and NH4NO3. Using a triple concentration of KH2PO4 (510 mg l-1) during the first week of adaptation and a fullconcentration of NH4NO3 (1650 mg l-1) over the next 2 weeks ensures 100% acclimatization of stevia regenerants to ex vitro conditions. The replacement of agar in the nutrient medium with a perlite-vermiculite mixture in the ratio of 1 : 3 stimulated the transition of regenerants to the photomyxotrophic type of nutrition. The use of a porous substrate provided a decrease in humidity inside the culture vessels, which led to forming both leaves with well-functioning stomata and a branched root system with root hairs. The stevia regenerants propagated in vitro on a porous substrate did not require special conditions for the ex vitro acclimatization. The yield of surviving plants in the greenhouse was 100%.