Nashir Uddin

Phosphorus is vital nutrient for the crop yield, and Breeding rice for tolerant to low phosphorus, efficient in uptake and assimilation is the best way for sustainable production. This study aimed to evaluate Bangladeshi rice cultivars and introgression lines (INLs) under phosphorus deficient soil to understand the genetic variation in deficiency tolerance. A total of 28 rice genotypes from various ecotypes such as Aus, Aman, Boro and Jhum and INLs were collected and grown in pot contained highly phosphorus deficient soil in the rooftop polythene shed house during October 2019 to March 2020. A phosphorus deficiency susceptible variety, IR 64, was used as control, and experiment was conducted following randomized complete block design with two replications. Biomass related traits such as dry weight (DW) and relative dry weight (RDW, %) were analyzed at early vegetative stage. Visual score based on the responses to artificial drought occurred due to absence of water for 5 consecutive days because of government imposed Covid-19 lockdown were also evaluated in a scale of 0 to 4. Plants showed wide variation in the measured traits in both in the phosphorus added normal or phosphorus deficient conditions. Two patterns of responses were observed. One pattern was similar to susceptible control IR 64 and another is highly sensitive to P- deficiency. Cluster analysis resulted four groups (I to IV). Group I consist of four rice varieties including Pathar kuchi, Lal dhan, INL-9, and INL-30, and showed low DW and low tolerances to phosphorus deficiency and artificial drought. Group II contain nine accessions including IR 64, Murali, Kuti Agrani, Kernaicha, and five INLs, and showed higher DW and susceptibility to phosphorus deficiency and artificial drought. Group III had medium DW and highly sensitive to phosphorus deficient condition and the accessions Kali jira and Aus (Awned) were included. Two jhum variety, Renkhoa Dhan and Galongpru, and seven INLs belong to the group IV which showed medium DW but tolerant to phosphorus deficiency and artificial drought compare to other groups. The genetic variations of DW and RDW under phosphorus deficient and artificial drought conditions were clarified among rice varieties in Bangladesh and INLs with IR 64 genetic background, and several varieties and INLs were found as the promising materials for further breeding program. Keywords: genetic variation, Phosphorus deficiency tolerance, rice, Relative Dry weight (RDW, %)

Phosphorus is vital nutrient for the plant growth, and inevitable to maintain the yield of rice. Current practices of chemical phosphorus fertilization is not sustainable because of its limited sources and non-renewable nature together with higher expenses. Breeding low phosphorus tolerant or resistant with higher uptake and assimilation efficient rice variety is the best alternative for sustainable production. This study aimed to evaluate the selected Bangladeshi rice germplasms and improved lines under phosphorus deficient soil to know their level of deficiency tolerance or resistance. A total of 28 rice genotypes from various ecotypes such as Aus, Aman, Boro and Jhum were collected and grown in pot contained highly phosphorus deficient soil in the rooftop polythene shed house during October 2019 to March 2020. A phosphorus deficiency susceptible variety, IR 64, was used as control, and experiment was conducted following randomized complete block design with two replications. Biomass related traits such as dry weight (DW) and relative dry weight (RDW, %) were analyzed at early vegetative stage. Visual score based on the responses to artificial drought occurred appeared due to absence of water for 5 consecutive days because of government imposed Covid-19 lockdown were also evaluated in a scale of 0 to 4. Plants showed wide variation in the measured traits in both in the phosphorus added normal or phosphorus deficient conditions. Two patterns of responses were observed. One patterns was similar to susceptible control IR 64 and another is highly sensitive to P- deficiency. Cluster analysis resulted four groups (I to IV). Group I consist of 4 rice cultivar including Pathar kuchi, lal dhan, INL-9 and 30, and showed lower DW under both phosphorus added & deficient conditions together with higher susceptibility to artificial drought. IR 64 belongs to the Group- II together with Murali, Kuti Agrani, Kernaicha and other 5 INLs. They have higher DW in phosphorus added condition but very low RDW in phosphorus deficient condition and also susceptible to artificial drought. Group III cultivars have medium DW under phosphorus added and low RDW under phosphorus deficient condition and Kali jira and Aus (Awned) are belong to this group. Two jhum variety, Renkhoa Dhan and Galongpru and 7 INLs are belong to the group IV which has moderate to high RDW under both phosphorus added and phosphorus deficient conditions. Rice cultivars of this group showed higher levels of tolerance to artificial drought and are promising for further breeding program to develop phosphorus deficiency tolerant variety.

Due to global population expansion and climate change impacts, the development of a stable yielding variety that adapts well to unfavorable conditions for rice cultivation, can contribute to sustainable and stable production in rice (Oryza sativa L.). Understanding genetic differentiations to ecotypes for rice cultivations, such as upland, rainfed lowland, and irrigated lowland, is very important to develop the breeding materials for adapting to each environmental condition. The upland landrace variety basically has low tiller/panicle numbers and a large panicle, and the plant architecture is different from that of the lowland variety. The tiller and panicle numbers have been considered as one of the most difficult traits for genetic changes artificially in rice breeding. A low tiller recessive gene ltn2 originated from a New Plant Type variety, IR 65600-87-2-23, harboring segments from an upland variety, Ketan Lumbu (Tropical Japonica Group), was found on chromosome 7, and the other QTLs for culm length, culm weight, panicle length, panicle weight, seed fertility, harvest index, and soil surface rooting were also detected in the same chromosome region. These low tiller genes and the other QTLs were estimated to play an important role in developing the architecture for upland rice. Some QTLs for root growth angle, DRO3 and qSFR7, were also found in the same chromosome region from upland varieties categorized into the Tropical Japonica Group, and the QTLs may also be relevant to upland adaptation together with other traits. Previous studies using high throughput re-sequencing (whole genome variation data) of a large batch of rice accessions could identify the ecotype differentiated genomic regions (EDRs) and Ecotype differentiated genes (EDGs) such as Os07g0449700, a type response regulator, which is critical in upland adaptation in the same region of chromosome 7. Two selective loci, E3735 and E4208, for upland and lowland differentiation, and their corresponding genes Os07g0260000 and Os07g0546500 were also detected on chromosome 7 by drought-responding EST-SSRs. These findings indicate that the region on chromosome 7 is highly possible to related to the plant shoot and root architecture in the upland rice variety that has an important role and differentiates between upland and lowland ecotypes.

Due to Covid-19, quarter a million patients have already died worldwide, and evidence showed a clear association between this death and multiple organ dysfunction cytokine storms. No sustainable remedy against this disease has been found and many solutions are being considered to dig out this virus by inventing humoral and cellular immunity capacity building methods as well as food-based remedies. COVID-19 has added an extra burden to the low-income country's health care system while they are still struggling with many challenges including malnutrition, sanitary, safe drinking water. Natural polyphenol engineering field crops (NPEF) based diet could help them to harness innate immunity to prevent or attenuate the SARS-Cov-2 infection as well as reducing the secondary/co-infection by bacteria and fungus of the hospitalized patients. Polyphenols are immunomodulators and have antibacterial, antiviral, anti-cancer, anti-diabetic, anti-inflammatory, coronary heart disease prevention effects together with the ability to transport other active molecules. Interaction of polyphenols increases the efficacy of vitamin D. This review explored the potentials of polyphenols and their available sources to address the chronic diseases including Covid-19 and proposed a food prescription for Bangladesh to improve their innate immunity system.

Due to Covid-19, quarter a million patients have already died worldwide, and evidence showed a clear association between this death and multiple organ dysfunction cytokine storms. No sustainable remedy against this disease has been found and many solutions are being considered to dig out this virus by inventing humoral and cellular immunity capacity building methods as well as food-based remedies. COVID-19 has added an extra burden to the low-income country's health care system while they are still struggling with many challenges including malnutrition, sanitary, safe drinking water. Natural polyphenol engineering field crops (NPEF) based diet could help them to harness innate immunity to prevent or attenuate the SARS-Cov-2 infection as well as reducing the secondary/co-infection by bacteria and fungus of the hospitalized patients. Polyphenols are immunomodulators and have antibacterial, antiviral, anti-cancer, anti-diabetic, anti-inflammatory, coronary heart disease prevention effects together with ability to transport other active molecules. Interaction of polyphenols increase efficacy of vitamin D. This review explored the potentials of polyphenols and their available sources to address the chronic diseases including Covid-19 and proposed a food prescription for Bangladesh to improve their innate immunity system.

The present study assesses the effect of drought stress on the Moringa biotype under magnetized water treatment (MWT). The Moringa biotype seedlings were subjected to drought stress with varying field capacities (FC) viz., control (100% FC), moderate drought stress (MS,50% FC), and severe drought stress (SS, 20% FC). Magnetized water (MW) significantly increased plant height, leaflet number, internode distances, leaf area, dry weight of the leaf, shoot, root of the seedlings and markedly improved the assimilation, transpiration, stomatal conductance, water use efficiency and vapor pressure deficit under drought stress conditions. The maximum quantum efficiency of PSII (Fv/Fm) and maximum chlorophyll fluorescence (Fm) were increased and minimum chlorophyll fluorescence (F₀) in the darkadapted state was decreased under drought stress with MWT. Photosynthetic pigments (Chl a, Chl b, carotenoids) significantly decreased under drought stress, but MW significantly increased them. The MW application in Moringa biotype resulted in a decrease in total phenolic content (TPC) by 19% and 26% under MS and SS conditions, respectively. Malondialdehyde(MDA), hydrogen peroxide(H₂O₂) and accumulation of proline in leaf were decreased with the prolongation of drought with MW. MW could be used for alleviating the drought stress in Moringa biotype seedlings and improve drought tolerance by modulating the physiological activities.

Phytoremediation is one of the safer, economical, and environment-friendly techniques in which plants are used to recover polluted soils, particularly those containing toxic organic substances and heavy metals. However, it is considered as a slow form of remediation, as plants take time to grow and flourish. Various amendments, including the augmentation of certain chemical substances i.e., ethylenediamine tetraacetic acid (EDTA), ethylene glycol tetra acetic acid (EGTA), and sodium dodecyl sulfate (SDS) have been used to induce and enhance the phytoextraction capacity in plants. Several reports show that chemical amendments can improve the metal accumulation in different plant parts without actually affecting the growth of the plant. This raises a question about the amount and mechanisms of chemical amendments that may be needed for potentially good plant growth and metal phytoremediation. This review provides a detailed discussion on the mechanisms undertaken by three important chemical amendments that are widely used in enhancing phytoremediation (i.e., EDTA, EGTA, and SDS) to support plant growth as well as soil phytoremediation. A core part of this review focuses on the recent advances that have been made using chemical amendments in assisting metal phytoremediation.

We investigated the effect of chemically disinfected wheat straw on the growth and yield of oyster mushroom (Pleurotus ostreatus). Various levels of treatments combined with different time (12, 18 and 24 hours) and dose of Formalin (250, 500 and 750ppm) and Bavistin (75ppm) were used, and the results were compared with the control. Compared to the control, almost all the treatments showed increased values, and among them significantly higher mycelium running rate, the lowest time from stimulation to primordial initiation and to harvest, number of primordial per packet, number of fruiting body per packet were found in treatment consists of 750ppm of Formalin with 75ppm of Bavistin for 18 hours. Length and diameter of the stipe, diameter and thickness of pileus, biological yield, economic yield, dry yield and biological efficiency were also significantly increased in this treatment. Wheat straw treated with 500ppm of Formalin with 75ppm of Bavistin for 18 hours performed best in terms of per cent protein and nitrogen content. However, weight of individual fruiting body was significantly higher when treated with 250ppm Formalin with 75ppm of Bavistin for 24 hours.As the sterilization of wheat straw using 750ppm of formalin with 75ppm of Bavistin for 18 hours could control pathogens and gave increased yield, this treatment might be useful as an economically effective treatment for the highest yield of oyster mushroom.

We characterized a rice introgression line, YTH34, harboring a chromosome segment from a New Plant Type (NPT) cultivar, IR65600-87-2-2-3, in the genetic background of an Indica Group elite rice cultivar, IR 64, under upland and irrigated lowland conditions in Japan. The number of panicles (as an indicator of tiller number) and number of spikelets per panicle of YTH34 were lower than those of IR 64 under irrigated lowland conditions, but both of those as well as culm length, panicle length, seed fertility, panicle weight, whole plant weight, and harvest index were dramatically reduced under upland conditions. And the low tiller of YTH34 was confirmed to start after the maximum tiller stage. In particular, the decrease of panicle number was remarkable in upland, so we tried to identify the chromosome location of the relevant gene. Through segregation and linkage analyses using F3 family lines derived from a cross between IR 64 and YTH34, and SSR markers, we found that low tiller number was controlled by a single recessive gene, ltn2, and mapped with the distance of 2.1 cM from SSR marker RM21950, in an introgressed segment on chromosome 7. YTH34 harboring ltn2 and the genetic information for DNA markers linked will be useful for genetic modification of plant architectures of Indica Group rice cultivar.