scholarly journals Investigation on frequency distribution of traditional rice landraces for drought tolerance at seedling stage

2020 ◽  
Vol 11 (03) ◽  
2013 ◽  
Vol 38 (4) ◽  
pp. 366-372
Author(s):  
Xiao-qing WANG ◽  
Mao-chang TANG ◽  
Jie HUANG ◽  
Zi-fan LIU ◽  
Juan XU ◽  
...  

2016 ◽  
Vol 67 (8) ◽  
pp. 2453-2466 ◽  
Author(s):  
Viktoriya Avramova ◽  
Kerstin A. Nagel ◽  
Hamada AbdElgawad ◽  
Dolores Bustos ◽  
Magdeleen DuPlessis ◽  
...  

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Melissa Ramdayal ◽  
Harro Maat ◽  
Tinde van Andel

Abstract Background Some 35,000 indentured laborers from India were recruited to work on plantations in Suriname between 1868 and 1916. It is likely that most were familiar with farming before they were shipped to this former Dutch colony in the Caribbean. Around 1900, those who did not return received a piece of land where most of them started growing rice as a staple crop. Agronomists characterized their traditional landraces as inferior and infested with weedy rice and started to ‘purify’ these landraces. No research has been done on whether these ancient rice varieties still exist. We aimed to document the rice varieties (both landraces and more modern cultivars) grown currently or in the recent past by (descendants of) Hindustani smallholders in Suriname, their origin, morphological and agronomic characters, local uses and cultural and spiritual relevance. Given the rapid decline in small-scale rice cultivation in the past 40 years, we wanted to know why people continued or abandoned rice farming and what aspects of traditional practices still survived. Methods We interviewed 26 (former) small-scale Hindustani farmers and asked about the varieties they cultivated and traditional agricultural practices. We collected seed samples, local names and associated information, and compared these to information from agricultural reports from the colonial period. We also interviewed 11 Maroons, one Javanese farmer, and three persons of mixed ethnicity, who were somehow involved in the cultivation of East Indian rice varieties. Results and discussion Hindustani smallholders in Suriname largely lost their traditional rice landraces. Most of the interviewed farmers grew modern cultivars, developed after 2000. Some cultivars from the 1950s were still planted for fodder, but these were heavily mixed with weedy rice and other weeds. Maroon farmers in the interior, however, still actively cultivated varieties with names like ‘coolie rice’, which probably descend from landraces introduced by the Indian contract laborers, although this needs to be confirmed by molecular research. Although traditional cultivation practices seem to have been lost, smallholders still retain pleasant memories of the manual planting, harvesting, and processing of rice, as well as the gender-based practices and beliefs associated with the cultivation of the crop. The oral history of former rice farmers and traditional rice varieties (possibly obtained from Maroon fields) could play a role in museum settings as living vehicles for memories of the descendants of Asian contract labourers in Suriname and Guyana.


2020 ◽  
Author(s):  
R. Anupriya ◽  
Sugitha Thankappan ◽  
A. Senthil ◽  
D. Rajakumar ◽  
Geetha S ◽  
...  

Abstract Seed germination plays a critical role in determining rice productivity under drought stress. We evaluated 100 traditional rice landraces originated from different agro-ecological zones of Tamil Nadu along with drought- susceptible (IR 64) and drought- tolerant (IR 64 DRT) checks. Moisture stress was induced using PEG 6000 and screening done over a range of osmotic potentials (-) 10 bars, (-) 12.5 bars and (-)15 bars for a period of 5 d. Physio-morphological traits such as germination rate, survival per cent, root and shoot length, vigor index, RS ratio and relative water content (RWC) were assessed during early drought stress. We observed significant changes in the seed macromolecules, phytohormone levels (GA and IAA), osmolytes and antioxidant responses (catalase and superoxide dismutase) between drought stress and control treatments. Kuliyadichan registered significantly higher IAA and GA (44% and 35% respectively over drought tolerant check IR 64 DRT) at drought stress, whereas all the landraces showed an elevated catalase activity. In PC analysis, first three PCs captured 88.93% of the total variation; significant differences were detected among genotypes with respect to the studied parameters. Six traditional landraces such as Kuliyadichan, Rajalakshmi, Sabhagidhan, Nootripathu, Chandaikar and Mallikar were selected and their inherent drought tolerance was associated with metabolic responses viz., triggered hydrolytic enzyme activities, hormonal cross-talk, ROS signaling and catalase under drought stress compared to drought sensitive IR64. Hence, these genotypes can be used as potential donor candidates towards genetic improvement of drought tolerance in rice.


2020 ◽  
Vol 18 (1) ◽  
pp. 1-10
Author(s):  
Florence L. Zapico ◽  
Josefina T. Dizon ◽  
Teresita H. Borromeo ◽  
Kenneth L. McNally ◽  
Edwino S. Fernando ◽  
...  

AbstractThis paper examines genetic erosion in rice landraces thriving in traditional smallholder agricultural systems in the Sarangani uplands, Philippines. In these marginal areas, the crop is closely interwoven with tribal culture and is vital in ensuring food security among upland households. Field visits unveiled high varietal diversity for upland rice and a rich tapestry of indigenous knowledge associated with its cultivation and use. Study results, however, revealed the tapering of the crop's genetic base due to farmers' changing priorities, pest infestation, weakening seed supply systems, shift to cash crops, natural calamities, environmental degradation, government programmes and peace and order problems. Consequently, these pressures undermined traditional agricultural systems in Sarangani upland communities causing food and water scarcity, hunger and suffering on a catastrophic scale. Interdisciplinary strategies aimed at simultaneously averting further varietal losses and environmental degradation while improving human well-being are therefore warranted. Furthermore, making traditional rice farming a lucrative endeavour will induce the younger generation to remain in the uplands and choose farming as a profession. This way, biocultural restoration of agriculture will be attained and the continued presence of the tribal groups in the Sarangani uplands will be ensured for a very long time.


Agronomy ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 882
Author(s):  
Dhananjay Kumar ◽  
Sandeep Kushwaha ◽  
Chiara Delvento ◽  
Žilvinas Liatukas ◽  
Vivekanand Vivekanand ◽  
...  

Drought stress is one of the key plant stresses reducing grain yield in cereal crops worldwide. Although it is not a breeding target in Northern Europe, the changing climate and the drought of 2018 have increased its significance in the region. A key challenge, therefore, is to identify novel germplasm with higher drought tolerance, a task that will require continuous characterization of a large number of genotypes. The aim of this work was to assess if phenotyping systems with low-cost consumer-grade digital cameras can be used to characterize germplasm for drought tolerance. To achieve this goal, we built a proximal phenotyping cart mounted with digital cameras and evaluated it by characterizing 142 winter wheat genotypes for drought tolerance under field conditions. The same genotypes were additionally characterized for seedling stage traits by imaging under controlled growth conditions. The analysis revealed that under field conditions, plant biomass, relative growth rates, and Normalized Difference Vegetation Index (NDVI) from different growth stages estimated by imaging were significantly correlated to drought tolerance. Under controlled growth conditions, root count at the seedling stage evaluated by imaging was significantly correlated to adult plant drought tolerance observed in the field. Random forest models were trained by integrating measurements from field and controlled conditions and revealed that plant biomass and relative growth rates at key plant growth stages are important predictors of drought tolerance. Thus, based on the results, it can be concluded that the consumer-grade cameras can be key components of affordable automated phenotyping systems to accelerate pre-breeding for drought tolerance.


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