Water use pattern and related agrometeorological indices of rabi & kharif sunflower (Helianthus annuus L.) at Deccan plateau

The agrometeorological data pertinent to estimation of water use and related agrometeorological indices of KBSH - II (1988 to 1991) and MORDEN varieties of sunflower (1992 and 1993) cultivated both in rabi and kharif seasons, were used to understand the comparative water use pattern and agrometeorological indices for getting an idea about the crop condition at Bangalore. The study revealed that mean weekly water use was higher in almost all the years during the kharif season than during the rabi season except in 1990 and the consumptive water use increased with development of the vegetative cover of the crop reaching a peak value in the vegetative growth stage. The ARI (agroclimatic rainfall index) and cumulative YMI (yield moisture index) were always higher during the kharif season than correspondingly those during the rabi season and showed yearly and seasonal variability in different growth stages which was due to the moisture stress condition of the soil as well as prevailing weather conditions of the atmosphere. In case of AI (aridity index), high values were observed at early and late crop growth stages during the kharif season which showed that the crop experienced less aridity between vegetative to seed formation stage. The water use efficiency (WUE) of the crop also revealed wide variation due to variety and season.

The Effectiveness of the Sexual Reproduction in Selected Clonal and Nonclonal Species of the Genus Ranunculus

Generative processes have been evaluated in six European buttercup species in order to verify the hypothesis that the reproduction efficiency of clonal species is lower than that of nonclonal ones. The study covered common species (Ficaria verna, Ranunculus auricomus, R. bulbosus, R. cassubicus, R. lanuginosus) and the endangered R. illyricus. The following properties have been assessed: pollen viability (staining method), pollen grain germination and the pollen-tube elongation in pistil tissues (fluorescence microscopy), seed formation efficiency, seed viability (tetrazolium test) and germination ability by introducing factors interrupting dormancy (low temperature and gibberellin application). Additionally, the pistil morphology was documented for R. bulbosus, R. illyricus and R. cassubicus using SEM techniques. It was demonstrated that the reproductive efficiency, expressed as the production of viable seeds able to germinate, was significantly higher in the species reproducing sexually (especially in R. lanuginosus) compared to the clonal ones. However, the complexity observed leads to separation of an additional group (cluster) of apomictic species: R. auricomus and R. cassubicus, distinguished by the lowest pollen viability and a low ability of the seeds to germinate. In the vegetatively reproducing R. illyricus, the seed formation efficiency was just 13.2% despite the having highest number of pistils in its flowers. The developed seeds of this species observed in our experiment were viable, but in general effective methods to stimulate their germination have not been proposed yet. Here, the first comparative study concerning the biology of sexual reproduction of R. illyricus is presented in the context of its decreasing distribution in natural habitats.

Assessment of tea plant (Camellia sinensis L.) accessions for pollen sources in natural crossing by using microsatellites

Tea (Camellia sinensis L. [O.] Kuntze) is a highly cross-pollinated and self-incompatible plant. Seeds can be harvested from specific individual mother plants in polyclonal tea gardens. Whether the pollen donor plays an important role in seed formation remains unclear. This study aimed to identify the male parents of 72 natural hybridized progenies (F1) from one female parent on the basis of a putative specific allele by using simple-sequence repeat (SSR) markers and the exclusion-likelihood method with Cervus 3.0 software. The genetic material, which comprised seven accessions of C. sinensis L., was acquired from Assamica planted in the Kayulandak polyclonal seed garden of the Pagilaran tea plantation in Batang District, Central Java, Indonesia, and was studied during 2019 and 2020. The genotype PGL-15 was used as the female parent, whereas the six candidate genotypes PGL-10, GMB-9, GMB-7, TPS-93, GMB-11, and TRI-2025 were used as the male parents. In this study, 13 SSR loci were used to identify the male parents of the F1 progenies obtained through natural hybridization between one female and six male tea accessions. Results indicated that the exclusion-likelihood method, which correctly predicted 100% of the male parents, was more effective than the putative specific allele approach, which correctly predicted only 34.72% of the male parents in the 72 hybridized F1 progenies of tea plants.

Recyclable, Antibacterial, Isoporous Through-Hole Membrane Air Filters with Hydrothermally Grown ZnO Nanorods

Reusable, antibacterial, and photocatalytic isoporous through-hole air filtration membranes have been demonstrated based on hydrothermally grown ZnO nanorods (NRs). High-temperature (300~375 °C) stability of thermoset-based isoporous through-hole membranes has enabled concurrent control of porosity and seed formation via high-temperature annealing of the membranes. The following hydrothermal growth has led to densely populated ZnO NRs on both the membrane surface and pore sidewall. Thanks to the nanofibrous shape of the grown ZnO NRs on the pore sidewall, the membrane filters have shown a high (>97%) filtration efficiency for PM2.5 with a rather low-pressure (~80 Pa) drop. The membrane filters could easily be cleaned and reused many times by simple spray cleaning with a water/ethanol mixture solution. Further, the grown ZnO NRs have also endowed excellent bactericidal performance for both Gram-positive S. aureus and Gram-negative S. enteritidis bacteria. Owing to the wide bandgap semiconductor nature of ZnO NRs, organic decomposition by photocatalytic activity under UV illumination has been successfully demonstrated. The reusable, multifunctional membrane filters can find wide applications in air filtration and purification.

Long- and Short-Term Temporal Variability in Cloud Condensation Nuclei Spectra in the Southern Great Plains

When aerosol particles seed formation of liquid water droplets in the atmosphere, they are called cloud condensation nuclei (CCN). Different aerosols will act as CCN under different degrees of water supersaturation (relative humidity above 100 %) depending on their size and composition. In this work we build and analyze a best-estimate CCN spectrum product, tabulated at ~45 min resolution, generated using high quality data from eight independent instruments at the US Department of Energy Atmospheric Radiation Measurement (ARM) Southern Great Plains site. The data product spans a large supersaturation range, from 0.0001 to ~30 %, and time period, 5 years from 2009–2013 and is available on the ARM data archive. We leverage this added statistical power to examine relationships that are unclear in smaller datasets. Probability distributions of many aerosol and CCN metrics are found to exhibit skewed log-normal distribution shapes. Clustering analyses of CCN spectra reveal that the primary drivers of CCN differences are aerosol number size distributions, rather than hygroscopicity or composition, especially at supersaturations above 0.2 %, while also allowing for simplified understanding of seasonal and diurnal variations in CCN behaviour. The predictive ability of using limited hygroscopicity data with accurate number size distributions to estimate CCN spectra is investigated and uncertainties of this approach are estimated. Finally, the dynamics of CCN spectral clusters and concentrations are examined with cross-correlation and autocorrelation analyses, which assist in determining the time scales of changing CCN concentrations at different supersaturations and are important for cloud modelling studies.

Thermal indices in relation to crop phenology and seed yield of pigeon pea (Cajanus cajan L. Millsp.) grown in the north bank plains zone of Assam

Two varieties of pigeon pea viz., BC (local) and ICPL 88039 were grown on the sandy loam soils of AICRPDA research farm of B. N. College of Agriculture, AAU in two consecutive kharif seasons of 2012-13 to 2013-14. Both the cultivars were sown on three different dates at ten days interval starting from 3rd June to 23rd June. GDD accumulation for attaining different phenological events viz., emergence, initiation of 1st flower bud and flower appearance, 50 per cent flowering, 1st pod formation, 1st seed formation and physiological maturity were worked out. The cumulative GDD accumulations up to physiological maturity were relatively higher in BC (local) which varied from 3395.6 to 3593.5 °C day, whereas, in ICPL 88039, it varied from 2945.0 to 3296.7 °C day in different sowings and seasons. A decreasing trend in accumulated GDD for attaining any Phenological event was observed with successive delay in sowings in both the cultivars in the two seasons. In both the crop seasons, Pheno-Thermal Index (PTI) varied from 16.67 to 18.18 °C day growth day-1, in BC (local) and 18.31 to 19.11 °C day growthday-1 in ICPL 88039 during the vegetative growth period under all the sowing dates while, in the reproductive growth stage, it was comparatively lower and ranged from 7.96 to 8.23 °C day growthday-1 in BC (local) and 10.28 to 11.87 °C day growthday-1 in ICPL 88039. Seed yield heat use efficiency (HUE) in BC (local) varied from 0.207 to 0.296 kg ha-1 °Cday-1, whereas, in ICPL 88039 it varied from 0.201 to 0.312 kg ha-1°Cday-1 under different sowing dates in both crop seasons. Seed yield heat use efficiency was relatively higher in 2013-14 followed by 2012-13 in both the cultivars which indicated the significant differences in using the heat, available to the plants.

Albinism in F1 Hybrids Hinders Geneflow Between Cultivated Chickpea (Cicer arietinum L.) and the Tertiary Gene Pool Species, Cicer Pinnatifidum

Wild Cicer species, especially those in the tertiary gene pool, carry useful alleles for chickpea improvement. The aim of this study was to evaluate the crossability and geneflow between three chickpea cultivars (as female parents) and four cross-incompatible Cicer pinnatifidum accessions (as pollen parents) from the tertiary gene pool. Ten crosses were conducted. One fully developed healthy F1 seed was harvested in vivo from the ICC 4958 × ICC 17269 cross, but the seedling developed an albino phenotype at 4–5 days after germination. Unlike other crosses, those involving the cultivar ICCV 96030 generated a large number of pods with comparatively large ovules. One albino plantlet was obtained from the ICCV 96030 × ICC 17269 cross by embryo rescue. Crosses involving ICCV 10 resulted in flower drop and poor pod set. These variable genotype-specific responses of pod, ovule, and seed development indicate that genetic factors affect the formation of interspecific hybrids. Although pod and seed formation in these interspecific crosses can be improved, geneflow between these materials is hindered by a strong genetic factor conferring albinism in the F1 hybrids.

Rapidly evolving genetic features for desert adaptations in Stipagrostis pennata

Background Stipagrostis pennata is distributed in the mobile and semi-mobile sand dunes which can adapt well to extreme environments such as drought and high temperature. It is a pioneer plant species with potential for stabilizing sand dunes and ecological restoration. It can settle on moving sand dunes earlier than other desert plants. It can effectively improve the stability of sand dunes and help more plants settle down and increase plant diversity. However, despite its important ecological value, the genetic resources available for this species are limited. Results We used single-molecule real-time sequencing technology to obtain the complete full-length transcriptome of Stipagrostis pennata, including 90,204 unigenes with an average length of 2624 bp. In addition, the 5436 transcription factors identified in these unigenes are rich in stress resistance genes, such as MYB-related, C3H, bHLH, GRAS and HSF, etc., which may play a role in adapting to desert drought and strong wind stress. Intron retention events are abundant alternative splicing events. Stipagrostis pennata has experienced stronger positive selection, accelerating the fixation of advantageous variants. Thirty-eight genes, such as CPP/TSO1-like gene, have evolved rapidly and may play a role in material transportation, flowering and seed formation. Conclusions The present study captures the complete full-length transcriptome of Stipagrostis pennata and reveals its rapid evolution. The desert adaptation in Stipagrostis pennata is reflected in the regulation of gene expression and the adaptability of gene function. Our findings provide a wealth of knowledge for the evolutionary adaptability of desert grass species.

Genome-Wide Association Study to Map Genomic Regions Related to the Initiation Time of Four Growth Stage Traits in Soybean

The time to flowering (DF), pod beginning (DPB), seed formation (DSF), and maturity initiation (DMI) in soybean (Glycine max [L.] Merr) are important characteristics of growth stage traits (GSTs) in Chinese summer-sowing soybean, and are influenced by genetic as well as environmental factors. To better understand the molecular mechanism underlying the initiation times of GSTs, we investigated four GSTs of 309 diverse soybean accessions in six different environments and Best Linear Unbiased Prediction values. Furthermore, the genome-wide association study was conducted by a Fixed and random model Circulating Probability Unification method using over 60,000 single nucleotide polymorphism (SNP) markers to identify the significant quantitative trait nucleotide (QTN) regions with phenotypic data. As a result, 212 SNPs within 102 QTN regions were associated with four GSTs. Of which, eight stable regions were repeatedly detected in least three datasets for one GST. Interestingly, half of the QTN regions overlapped with previously reported quantitative trait loci or well-known soybean growth period genes. The hotspots associated with all GSTs were concentrated on chromosome 10. E2 (Glyma10g36600), a gene with a known function in regulating flowering and maturity in soybean, is also found on this chromosome. Thus, this genomic region may account for the strong correlation among the four GSTs. All the significant SNPs in the remaining 7 QTN regions could cause the significant phenotypic variation with both the major and minor alleles. Two hundred and seventy-five genes in soybean and their homologs in Arabidopsis were screened within ± 500 kb of 7 peak SNPs in the corresponding QTN regions. Most of the genes are involved in flowering, response to auxin stimulus, or regulation of seed germination, among others. The findings reported here provide an insight for genetic improvement which will aid in breeding of soybean cultivars that can be adapted to the various summer sowing areas in China and beyond.

Expression Analysis of MaTGA8 Transcription Factor in Banana and Its Defence Functional Analysis by Overexpression in Arabidopsis

TGA transcription factor is a member of the D subfamily of the basic region-leucine zippers (bZIP) family. It is a type of transcription factor that was first identified in plants and is the main regulator in plant development and physiological processes, including morphogenesis and seed formation in response to abiotic and biotic stress and maintaining plant growth. The present study examined the sequence of the MaTGA8 transcription factor, the sequence of which belonged to subfamily D of the bZIP and had multiple cis-acting elements such as the G-box, TCA-element, TGACG-element, and P-box. Quantitative real time polymerase chain reaction (qRT-PCR) analyses showed that MaTGA8 was significantly down-regulated by the soil-borne fungus Fusarium oxysporum f. sp. cubense race 4 (Foc TR4). Under the induction of salicylic acid (SA), MaTGA8 was down-regulated, while different members of the MaNPR1 family responded significantly differently. Among them, MaNPR11 and MaNPR3 showed an overall upward trend, and the expression level of MaNPR4, MaNPR8, and MaNPR13 was higher than other members. MaTGA8 is a nuclear-localized transcription factor through strong interaction with MaNPR11 or weaker interaction with MaNPR4, and it is implied that the MaPR gene can be activated. In addition, the MaTGA8 transgenic Arabidopsis has obvious disease resistance and higher chlorophyll content than the wild-type Arabidopsis with the infection of Foc TR4. These results indicate that MaTGA8 may enhance the resistance of bananas to Foc TR4 by interacting with MaNPR11 or MaNPR4. This study provides a basis for further research on the application of banana TGA transcription factors in Foc TR4 stress and disease resistance and molecular breeding programs.