In an age of anthropocene, shifting plant phenology is one of the most striking biological indicators of global environmental change. Majority of the studies reporting shifts in plant phenology are ...available from the North America and Europe and largely scarce from the developing world, including the Himalaya; and studies integrating multiple methodological approaches to investigate the climate-driven phenological shifts are too rare. Here, we report the shifts in spring flowering phenology of model plant species, Sternbergia vernalis in response to the changing climate in Kashmir Himalaya, by integrating decadal field observational records with long-term herbarium and dated-photograph data, and supported with experimental evidences. Our results revealed a significant increasing trend of 0.038, 0.016 and 0.023 °C/year in the annual mean maximum temperature (Tmax), mean minimum temperature (Tmin) and diurnal temperature range (DTR) respectively; but an insignificant decreasing trend in annual precipitation of −1.24 mm/year over the last four decades (1980–2019) in this Himalayan region. The flowering phenology of S. vernalis has significantly advanced by 11.8 days/°C and 27.8 days/°C increase in Tmax and Tmin respectively, indicating that the climate warming has led to substantial shifts in flowering phenology of the model plant species. We also observed a strong association of seasonal Tmax (December–February) and DTR on the early onset of spring flowering, however precipitation had no significant effect on the timing of flowering. The greenhouse experiment results further supported a significant effect of temperature in triggering the phenological shifts, wherein the model plant grown under different temperature treatments flowered 9–20 days earlier compared to the control. Our study showcases the integrated use of multiple methodological approaches for unravelling the long-term phenological shifts in response to climate change, and contributes in filling the knowledge gaps in the phenological research from the developing world in general and the Himalaya in particular.
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•We report shifts in spring flowering phenology driven by changing climate in the Himalaya.•Flowering advanced by 11.8 and 27.8 days/°C increase in Tmax and Tmin respectively.•Seasonal Tmax (December–February) and DTR strongly determined early onset of flowering.•Experimental evidence shows effect of warmer temperature in the phenological shifts.•Our study showcases the use of multiple methods in phenology research.
Climate warming-driven temporal shifts in phenology are widely recognised as the foremost footprint of global environmental change. In this regard, concerted research efforts are being made worldwide ...to monitor and assess the plant phenological responses to climate warming across species, ecosystems and seasons. Here, we present a global synthesis of the recent scientific literature to assess the progress made in this area of research. To achieve this, we conducted a systematic review by following PRISMA protocol, which involved rigorous screening of 9476 studies on the topic and finally selected 215 studies for data extraction. The results revealed that woody species, natural ecosystems and plant phenological responses in spring season have been predominantly studied, with the herbaceous species, agricultural ecosystems and other seasons grossly understudied. Majority of the studies reported phenological advancement (i.e., preponement) in spring, followed by also advancement in summer but delay in autumn. Methodology-wise, nearly two -third of the studies have employed direct observational approach, followed by herbarium-based and experimental approaches, with the latter covering least temporal depth. We found a steady increase in research on the topic over the last decade with a sharp increase since 2014. The global country-wide scientific output map highlights the huge geographical gaps in this area of research, particularly in the biodiversity-rich tropical regions of the developing world. Based on the findings of this global synthesis, we identify the current knowledge gaps and suggest future directions for this emerging area of research in an increasingly warming world.
Drought and limited availability of water serve as the serious limitation for rice production in rainfed ecosystems. Among the major rainfed rice-cultivating areas, states of eastern India occupy one ...of the largest drought-prone ecologies in the world. Cultivating drought tolerant rice varieties can serve as the most coherent approach to ensure food security in these areas. International Rice Research Institute (IRRI), along with its national collaborators, has developed drought tolerant rice varieties possessing high yield along with desirable grain quality. One such conventionally bred line, IR74371-70-1-1, has been released with different names in the different countries: in India as Sahbhagi Dhan, in Nepal as Sukha Dhan 3, and in Bangladesh as BRRI Dhan 56. This indicates the suitability of this line to show better performance across the wide range of environments. Sahbhagi Dhan is a short duration variety that has genetic drought tolerance and is more efficient at extracting available moisture from the soil. During drought years, farmers cultivating Sahbhagi Dhan obtained the yield advantage of 0.8 to 1.6 t ha−1 over currently grown long duration as well as traditional varieties. In 2012, when the paddy crop was hit by drought, Sahbhagi Dhan revealed the yield advantage of more than a t ha−1, which reduced to 0.78 and 0.56 t ha−1 during non-drought years of 2013 and 2014, respectively. Data taken from head to head trials during 2017 showed that Sahbhagi Dhan exhibited better performance over the existing rice varieties grown by farmers even under non-drought conditions. The important feature of Sahbhagi Dhan is its evident impact under drought and no yield penalty under favorable conditions over the counterfactual varieties of the same duration. Along with better yield under drought, the important advantage of Sahbhagi Dhan is the short maturity duration of this variety. This allows the farmers to advance the succeeding crop and creates an opportunity for accommodating an additional crop under favorable rainfed ecology, thereby enhancing the cropping intensity. Since the majority of the farmers living in drought prone ecologies are socio-economically under privileged, Sahbhagi Dhan, along with other drought tolerant varieties, can serve as one of the most viable and deliverable technologies for eradicating poverty from these ecologies dependent on rainfed rice.
Experimental evidences in support of climate warming–driven phenological shifts are still scarce, particularly from the developing world. Here, we investigated the effect of experimental warming on ...flowering phenology of selected woody plants in Kashmir Himalaya. We selected the twigs of four congeneric pairs of temperate woody species (
Prunus
,
Populus
,
Ulmus
,
Viburnum
)—typical spring-flowering plants in the region. Using randomised block design, we monitored these winter dormant twigs in controlled growth chambers to study the effect of different temperature regimes (9, 17, 20 and 23 °C) and species identity on the patterns of phenological shifts. We observed a significant phenological shift in all the species showing preponement in the first flower out and senescence phases ranging from 0.56 to 3.0 and 0.77 to 4.04 days per degree increase in temperature, respectively. The duration of flowering phase in all the species showed a corresponding decrease along the gradient of increasing temperature, which was more driven by preponement of the flower senescence than the start of flowering. The patterns of phenological shifts were highly species-specific, and the magnitude of these shifts significantly varied in all the four pairs of congeneric species despite their phylogenetic similarity. Our study provides experimental support to the previous long-term observation and herbarium-based studies showing that the patterns of phenological shifts in response to global climate warming are likely to vary between species, even those belonging to same evolutionary stock. Our findings highlight that a one-size-fits-all strategy to manage the likely impacts of climate warming–induced phenological shifts will seldom succeed, and should instead be designed for the specific phenological responses of species and regions.
Abstract Rice–wheat rotation is the principal cropping system in South Asian countries. Increasing productivity under this cropping system in Northern India is not only a policy priority but also an ...important component towards ensuring food and nutritional security for the major portion of the Indian population. The objective of enhanced productivity is being pursued through innovative extension models focusing on the adoption of modern varieties and community-led seed production. The present experimental study (a randomized control trial) was conducted in Uttar Pradesh (India) to evaluate the efficacy of community institutions e.g., women self-help group (WSHG) based seed interventions in promoting the adoption of improved varieties amongst farmers. Besides, the impact on the implementation of quality seed production practices, adoption of seed quality measures, and participation in capacity-building trainings were also evaluated. The findings infer that implementing seed scaling programs through community institutions leads to a significantly higher rate of technological adoption than that executed through non-collectivized ways. Besides, farmers from WSHGs have more tendency towards learning new technologies and participating in training programs about improved crop management practices. The study also explains that WSHG-based programs are not a contributory factor in advancing farm technologies that are already in practice, such as seed cleaning and germination tests. This validated model can be suitably replicated for accelerated dissemination of seed-related innovations.
Flooding is one of the major constraints for rice production in rainfed lowlands, especially in years and areas of high rainfall. Incorporating the Sub1 (Submergence1) gene into high yielding popular ...varieties has proven to be the most feasible approach to sustain rice production in submergence-prone areas. Introgression of this QTL into popular varieties has resulted in considerable improvement in yield after flooding. However, its impact under non-flooded conditions or years have not been thoroughly evaluated which is important for the farmers to accept and adopt any new version of their popular varieties. The present study was carried out to evaluate the effect of Sub1 on grain yield of rice in different genetic backgrounds, under non-submergence conditions, over years and locations. The study was carried out using head to head trials in farmer's fields, which enable the farmers to more accurately compare the performance of Sub1 varieties with their recurrent parents under own management. The data generated from different head to head trials revealed that the grain yield of Sub1 varieties was either statistically similar or higher than their non-Sub1 counterparts under non-submergence conditions. Thus, Sub1 rice varieties show no instance of yield penalty of the introgressed gene.
Adoption of any agricultural technology depends upon the way in which farmers are being informed about its benefits. Educational status, caste, gender and other social issues also play a significant ...role in the adoption process. To evaluate the impact of trainings on quality seed production, access to the climate resilient rice seeds, availability of information about seed sources and use of IRRI super bags, a randomized experimental research was carried out over a period of two years across five different states of India. The baseline and a follow-up survey was conducted to capture the farming practices followed by during wet seasons of 2016 and 2017, respectively. The impact of trainings, seed use, information given and agro-based goods was evaluated by comparing the adoption behaviour of treatment and control farmers. There was an increase (28.8%) in the practice of using salt solution to clean seeds primarily due to the impact of quality seed production (QSP) trainings. Female farmers responded more than the male farmers as number of women adopting the practice was higher than men. The impact of the trainings on farmers' knowledge and adoption of climate resilient/stress tolerant rice varieties (STRV) was also more pronounced on females than on male farmers. Farmers’ access to seeds substantially enhanced the adoption and reusability irrespective of the gender. Similarly, the information delivered to the farmers was quite economical in enhancing the awareness and adoption of climate resilient rice, but the effect was predominantly driven by female farmers. Female farmers performed relatively better with respect to the storing the new seeds in IRRI super bags. Thus, incentivising farmers in general and female farmers in particular can serve as a potential means to adopt agricultural technologies that have potential to boost rural economy and enhance the food security. The results are being supported by a rigorous empirical analysis.
•The study provides with evidence that an increase in seed cleaning practice is primarily due to the impact of trainings.•The information intervention is economical that enhances the adoption of new seeds and is mostly driven by female farmers.•Incentivising female farmers can serve as a potential means to boost rural economy and enhance the food security.
Rice is globally the most important food crop and there is a dire need to feed the ever-increasing population by improving its productivity. It has been realised that diseases are the major ...impediment towards enhancing the productivity of this crop. Despite the advent of modern effective disease control measures such as use of chemicals, bioagents and resistant varieties; agronomic practices still play a vital role in disease management in rice. Optimum use of different agro-techniques can be exploited for efficient control of various devastating diseases like rice blast, sheath blight, bakanae and many more by providing a favourable environment to better crop survival. Besides, appropriate selection of a variety, use of quality seed, method of establishment, planting time, nutrient, water and weed management practices can be well exploited to control various diseases. This manuscript entails to review the work pertaining to use of agronomic practices for exploiting the potential of crop environment interaction through reduced disease infection and to bridge the yield gap for ensuring sustained food security.
Background
Characterization and evaluation of plant genetic resources play an important role for their utilization in the crop improvement programmes.
Methods and results
This study involves the ...agro-morphological and cooking quality besides, molecular characterization of 51 genotypes/advance breeding lines of rice from Kashmir Himalayas. Significant variability was observed for all agro-morphological and cooking quality traits among all the studied genotypes. Cluster analysis using UPGMA method divided the genotypes into two major clusters having 15 and 36 genotypes. Thirty eight genotypes screened using 24 SSR markers detected 48 alleles with 2.0 alleles for each locus with average polymorphism information content (PIC) of 0.37. High polymorphism information content (PIC) values was observed for the primers RM263 (0.67), RM159 (0.59) and RM333 (0.50). Furthermore, out of 38 SSR markers screened on 192 temperate rice germpalsm lines, R4M17 accurately differentiated indica and temperate japonica genotypes amplifying 220 bp and 169 bp, respectively. Accordingly, 15 genotypes were reported as indica and 28 temperate japonica in addition to 149 genotypes as intermediate types.
Conclusion
The information on marker-based diversity and performance based on cooking quality and agronomic traits helped to select the most divergent lines for crossing. Also the analysis was useful to classify the temperate germplasm into indica and temperate japonica. The classification could be helpful to devise a strategy for inter-sub species hybridization to breed for improved rice varieties.
The grain size is considered to be one of the complex traits affecting rice yield as it is directed by multifaceted gene combinations. In the present experiment, 34 pollen parents were crossed with ...four female lines in line × tester matting design and 136 hybrids were generated. Wide phenotypic differences were observed across the hybrids for grain length, grain width and grain length-width ratio. The correlation analysis depicted a strong association among two grain size regulating traits viz., kernel length and kernel length-width ratio. However, kernel width shows negative correlation with these traits and influences the final grain size. The hybrids were also investigated at GS3 and GW8 loci. Gene based markers SF28 and DRR-GL showed strong association with the grain size related traits. The population structure analysis divided the entire material into four subgroups viz., I, II, III and IV with demarcation of long, homozygous and short grain types. The analysis of molecular variance (AMOVA) as well as a pairwise FST analysis indicated significant differentiation of population II as compared to rest of the populations, suggesting that only one among the four subgroups structured significantly different. Marker based evaluation in the present study provides the understanding for selection of suitable candidate markers for obtaining preferred grain shape/size and improving the grain yield through marker-assisted breeding.
Bangladesh J. Bot. 51(2): 343-351, 2022 (June)
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