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Consumers hesitate to purchase field-grown shoot-tops of amaranths in Sri Lanka, citing the low-cleanliness making growers focus on greenhouse farming. However, the photosynthetic and growth variations in relation to the organoleptic preference of the greenhouse-grown amaranths in comparison to field-grown counterparts have not been studied. Also, the species delimits of the amaranths in Sri Lanka have not been identified, limiting our ability to interpret species-specific production characteristics. Thus, we assessed the common types of amaranths under greenhouse and field conditions. The photosynthesis was measured using a MultispeQ device of the PhotosynQ phenomic platform, which records chlorophyll fluorescence-based parameters. The shoot-tops were harvested and prepared as dishes according to the typical recipe for amaranths in Sri Lanka. The dishes were subjected to an organoleptic assessment for the parameters color, aroma, bitterness, texture, and overall taste. The differences in plant and the shoot-top biomass were also assessed. The markers atpB-rbcL, matk-trnT, and ITS were used to define the species delimits. The field-grown and greenhouse-grown amaranths exhibited species/cultivar-specific photosynthetic variations. The texture and overall taste of the dishes were different among greenhouse and field-grown material. The tasters preferred the texture and the overall taste of the greenhouse-grown shoot-tops. The greenhouse-grown plants also yielded higher shoot-top harvests compared to field-grown counterparts. Out of the tested markers, ITS defines the delimits of amaranth species. The higher organoleptic preference, the appreciable yield levels, unique photosynthetic patterns of the greenhouse-grown amaranths, and species definitions provide the much-needed platform for clean shoot-top production guaranteeing the highest end-user trust.

the development of rice cultivars with desirable traits is essential. the decision-making is a crucial step in rice breeding programs. Breeders can make efficient and pragmatic decisions if an organized pedigree visualization platform is available for the accessions and cultivars in rice breeding germplasm. in the present study, the available data of all the rice varieties released by Rice Research and Development institute, Sri Lanka, and the related landraces and genotypes were arranged in pedimap, a pedigree visualization tool. pedimap can showcase pedigree relationships, phenotypic, and molecular data. the identity by descent probabilities were calculated using flexQtL software and included in the pedimap database. the parentage selection based on the variations of phenotypic traits, selection of marker alleles for molecular breeding, and detection of the founders of genetic effects can be swiftly conducted using Pedimap. However, the power of harnessing the value of pedimap for making breeding decisions relies on the availability of data for the traits, markers, and genomic sequences. thus, it is imperative to characterize the breeding germplasms using standard phenomic and genomic characterization procedures such as the assessment of before organized into Pedimap. Thereby, the worldwide breeding programs can benefit from each other to produce improved varieties to meet global challenges. Rice is one of the major crops in the world, with an annual production over 700 million metric tons 1. Half of the world population consumes rice as the staple food 2. Currently, the demand for rice is rapidly increasing due to the growth of the human population 3. However, the current rice production cannot meet the increasing demand causing severe food security issues. The biotic and abiotic stresses also exert a negative influence on rice production 4. The rice farming is also a way of living for many people, especially in numerous Asian countries 5. At present, 1.8 million Sri Lankan families engage in rice farming over 870,000 hectares 6. The annual rice production in Sri Lanka is approximately 2.3 million metric tons (MT), which is insufficient to fulfill the domestic rice demand of 3.0 million 7. Hence, the Sri Lankan government spends about USD 400 million to import rice annually 7,8. The rice production is mainly affected by drought and irregular rainfall patterns caused by climate change 9-11 , adverse soil conditions such as salinity 6,12 , and pest and disease attacks 13. The biotic and abiotic stresses in rice farming can be controlled using numerous agronomic practices such as irrigation, drainage, fertilization, and the application of pesticides. However, the rate of success of the controlling methods is limited 13 due to the unpredictable nature of climate change, soil degradation, variations in pest dynamics, and development of pest resistance 14. Therefore, breeding is considered as the most successful strategy to produce high yielding and stress-resilient rice varieties 15. The improved rice genotypes can...

Brown Planthopper (BPH), Nilaparvata lugens Stål, imposes a significant threat to the rice cultivation in Sri Lanka, generating 5-10% of annual yield losses. Rice farmers mainly adopt chemical methods to control the BPH attacks. The intensive use of insecticides is a crucial trigger for the development of resistance and hence continuous BPH outbreaks. Thus, the chemical methods of control do not provide a permanent solution to the BPH. The most recommended strategy of resolving the BPH crisis in rice is the development of resistant cultivars. Most of the Sri Lankan rice germplasm has already been screened for BPH resistance; however, reliable molecular breeding strategies must be implemented to acieve this target.Development of BPH resistant cultivars relies on utilizing appropriate genomic selection protocols in breeding schemes such as marker-assisted backcrossing.Therefore, a literature survey was carried out to evaluate BPH control methods and to emphasize the employment of backcross breeding with the genomic selection approach as a precise tool to develop BPH resistant rice varieties. The genetic basis of BPH resistance has been unravelled for many rice cultivars however, further screening is required to identify locally available resistant sources. The polymorphic markers for the foreground and background selection must be developed for the introgression of the BPH resistant genes and recovery of the recurrent parent genome. The validation of the markers developed in the international breeding and genetics programmes for the local germplasm is also an essential step prior to the genomic selection of BPH resistant rice varieties.

Brown planthopper, bacterial leaf blight and rice blast disease are identified as devastating stresses of rice cultivation. Developing host plant resistance is considered an effective and environmentally friendly management strategy. In Sri Lanka, limited studies have been carried out to assess the genetic basis of disease resistance. Bph3, Pikh and Xa21 genes convey significant resistance against biotic stresses. The current study was conducted to identify whether markers linked to Bph3, Pikh and Xa21 genes can facilitate the identification of resistant varieties. A total of 34 varieties were selected for the study and their morphometric and marker allelic data were subjected to descriptive and statistical analyses. Moderate height varieties depicted high yield. Most of the varieties showed significant moderate resistance against stresses. Molecular marker analysis yielded polymorphic banding patterns for all markers. RM 589 marker linked to Bph3 dominant gene provides overlapping banding patterns for the cultivars with different resistance levels making it impossible to discriminate resistant and susceptible cultivars. RM 206 marker linked to gene pikh provided the expected PCR product size for RM 206 marker is 147 bp. The resistant varieties gave band lengths of 140 bp, 170 bp and susceptible or moderately susceptible varieties produced band lengths of 160 bp and 155 bp. pTA 248 marker linked to Xa21 locus produced bands length of 670 bp, 740 bp and 930 bp. The 930 bp band was observed only in IRBB 60 variety. IRBB60 amplified 930 bp fragment confirms the possession of the resistant allele of Xa21 in its background. Presence of 730 bp indicates the susceptible allele. None of the Sri Lankan varieties carries a resistant allele for Xa21 as they have 730 bp allele for pTA 248. The rice varieties such as Bg251, Bg455, Bg450, Bg305, At402, At308 and At354 contain high yielding traits but need to improve for the pest and disease resistance.