Relationship between Seed Priming Mediated Seedling Vigor and Yield Performance of Spring Wheat

Seed priming is a pre-germinated technique that can enhance seed germination percentage,faster and synchro-nized germination,better seedling growth,and yield under stress conditions.To ascertain the most effective seed priming method that would ensure the potential yield of wheat in Bangladesh,two experiments were carried out from December 2021 to March 2022 at the Department of Agronomy,Bangladesh Agricultural University.Two wheat varieties namely BARI Gom-28 and BWMRI Gom-1 were subjected to a range of priming chemicals in both lab and pot tests.These compounds included the following:control(no priming),hydropriming(distilled water),10000 ppm KNO_(3),15000 ppm KNO_(3),40000 ppm Mannitol,60000 ppm Mannitol,10000 ppm NaCl,20000 ppm NaCl,100 ppm PEG,150 ppm PEG,500 ppm NaOCl,1000 ppm NaOCl,10000 ppm CaCl_(2),20000 ppm CaCl_(2),10000 ppm KCl and 20000 ppm KCl.A complete randomized design(CRD)with three repli-cations was used to set up the experiments.The results showed that BARI Gom-28 and BWMRI Gom-1 responded best to KCl priming in terms of rapid seed germination and strong seedling development.On the other hand,the best priming agents for plant growth and productivity turned out to be CaCl_(2) and KCL.The results of this study support the possibility of using seed priming as a technique to improve wheat plant development and output by raising seed emergence and survival rates.

Potentiality of Different Seed Priming Agents to Mitigate Cold Stress of Winter Rice Seedling

Seed priming has proved to be an effective pre-germination seed invigoration technique for different crops to improve seed and seedling performance under different abiotic stresses.In Bangladesh,winter rice is very often exposed to cold waves just after sowing in the nursery bed resulting in poor seed germination and seedling emergence,yellowish and thin seedlings production,and a very low survival rate.Seed priming may mitigate the cold stress during seed germination and seedling emergence and helps in the quality seedling production of winter rice.To evaluate the efficacy of different seed priming techniques in increasing seedling emergence,growth,vigor and survivability of winter rice cultivars under cold stress,a pot experiment was conducted at the Department of Agronomy,Bangladesh Agricultural University during December 2018 to January 2019.The experiment comprised two factors,(A)Winter rice variety namely,(i)BRRI dhan29 and (ii)BRRI dhan36;(B)Seed priming agent namely (i)Control(no priming),(ii)20000 ppm NaCl,(iii)30000 ppm NaCl,(iv)20000 ppm KCl,(v)30000 ppm KCl,(vi)20000 ppm CaCl2,(vii)30000 ppm CaCl2,(viii)50 ppm CuSO4,(ix)75 ppm CuSO_(4),(x)10000 ppm ZnSO4,(xi)15000 ppm ZnSO4,(xii)2 ppm Na2MoO4,(xiii)3 ppm Na2MoO4,(xiv)100 ppm PEG(Polyethylene glycol 4000)and (xv)150 ppm PEG.Seeds were sown on two different dates viz.,1st December and 1st January so that seedlings are exposed to cold stress at different stages.The experiment was laid out in a completely randomized design(CRD)with three replications.Results indicated that(in most of the cases)seed priming has a positive impact on seedling emergence rate(%),root length,shoot length,root shoot ratio,root dry weight,shoot dry weight,seedling dry weight and survival rate(%).Among the priming agents,KCl and CaCl2 performed best;while priming with NaCl and PEG showed no advantages over no priming for both the sowing dates.In general,BRRI dhan36 performed better than BRRI dhan29 in terms of seedling growth because of its higher tolerance to cold stress.But,both the varieties performed similarly in terms of emergence rate and survival rate.Thus,priming is an effective tool to increase seed germination,better seedling growth,and higher seedling survivability of winter rice under cold stress,and KCl(20000 ppm)or CaCl2(20000 ppm)can be considered as a viable priming agent.

Efficacy and Economics of Different Need Based Nitrogen Management Approaches in Winter Rice

This experiment aimed to study the efficacy of different nitrogen (N) management approaches in winter rice. The experiment consisted of two rice varieties: 1) BRRI (Bangladesh Rice Research Institute) dhan29-an inbred and 2) Dhanigold-a hybrid, and eight N management approaches: 1) BRRI recommended N (control), 2) Soil analysis based N management, 3) N application based on Agro-ecological zone, 4) 20 kg·N·ha-1 at ≤35 SPAD (Silicon photon activate diode) value, 5) 30 kg·N·ha-1 at ≤35 SPAD value, 6) 20 kg·N·ha-1 at ≤3.0 LCC (leaf colour chart) value, 7) 30 kg·N·ha-1 at ≤3.0 LCC value and 8) Urea Super Granule. Between two varieties, hybrid Dhani gold produced higher grain yield (6.67 t·ha-1) than the inbred BRRI dhan29. Application of 20 kg·N·ha-1 at ≤3.0 LCC value gave the highest grain yield (7.10 t·ha-1), whereas the lowest grain yield (5.92 t·ha-1) was found from the SPAD approach with 20 kg·N·ha-1 at ≤35 SPAD value. In case of treatment interaction highest grain yield (7.34 t·ha-1) was found in BRRI dhan29 coupled with 20 kg·N·ha-1 at ≤3.0 LCC value with 18 kg·N·savings·ha-1 over control, maximum gross income (146,800 BDT·ha-1) and net benefit (142,120 BDT·ha-1), which was statistically identical with the grain yield from the interaction of Dhani gold and 30 kg·N·ha-1 at ≤3.0 LCC value but required 42 kg·extra·N·ha-1 (over control). The lowest grain yield (5.19 t·ha-1) was found when Dhanigold was coupled with 30 kg·N·ha-1 at ≤35 SPAD value, while the 20 kg·N·application·ha-1 at ≤35 SPAD value gave moderate yield (6.87 t·ha-1) with considerable higher gross (139,600 BDT·ha-1) and net (136,090 BDT·ha-1) incomes than the control (gross: 121,000 and net: 115,600 BDT·ha-1). The results reveal that 20 kg·N·ha-1 at ≤3.0 LCC value appeared as the promising practice for inbred BRRI dhan29, and 30 kg·N·ha-1 at ≤35 SPAD value for hybrid Dhanigold in terms of yield, N use efficiency and economic benefit of winter rice.

Low-Cost Sustainable Technologies for the Production of Clean Drinking Water—A Review

Water has always been an important and life-sustaining drink to humans and is essential to the survival of all known organisms. Over large parts of the world, humans have inadequate access to drinking water and use water contaminated with disease vectors, pathogens or unacceptable levels of toxins or suspended solids. Drinking such water or using it in food preparation leads to widespread, acute and chronic illnesses and is a major cause of death and misery in many countries. The UN estimates that over 2.0 billion people have limited access to safe water and nearly 800 million people lack even the most basic supply of clean water. The main issue is the affordability of water purifying systems. Many people rely on boiling water or bottled water, which can be expensive. Therefore, technologies that are cost effective, sustainable, ease of operation/maintenance and the treatment processes with locally available materials are required. In this article, some unique low-cost sustainable technologies available/or in-use, i.e. natural filtration, riverbank filtration, biosand filtration, membrane filtration, solar water disinfection technique, biologically degradable materials such as moringa powder, scallop powder treatment, and biosand pitcher treatments have been discussed.

Allelopathy of Medicinal Plants: Current Status and Future Prospects in Weed Management

An attempt has been made in this article to accumulate and elucidate the literatures about the allelopathic potentiality of medicinal plants, and its role on the development of bio-herbicides for eco-friendly weed management strategies to conserve bio-diversity and ecological balance. This review paper has been prepared by comprehensive studies of various published research articles, books and proceedings available in the world literature. The farmers of different countries use several weed management techniques in order to minimize the deleterious effect of weeds. Among them most commonly used practice is application of herbicides due to its high efficacy and cost effectiveness, less time-consuming nature, flexibility and easy accessibility, and more rapid out return. Although use of synthetic herbicides in the crop fields has increased the crop production as well as the productivity by reducing the weed infestation, over time it causes a number of environmental hazards. Hence, to avoid these detrimental effects of synthetic herbicide, a lot of efforts have been dedicated by the researchers to search the novel natural plant products mainly allelochemicals and try to apply them as a tool for the development of bio-degradable natural herbicides. This paper intended to reflect the current state of allelopathic medicinal plants and their potentiality to develop eco-friendly and natural product-based herbicides for sustainable agriculture, and to invite further debate on this issue.

Allelopathic Potential of Three Oil Enriched Plants against Seedling Growth of Common Field Crops

Current study aims to investigate the allelopathic potential of the differentparts (leaf, bark, stem, twig and root) of three oil-enrich plant species ofBangladesh viz., Jatropha curcus, Ricinus communis and Aphanamixispolystachya. The aqueous extract of those plant parts were diluted intofour different concentrations viz., 1:5, 1:10, 1:15, 1:20 (w/v) and testedagainst the seedling growth of jute, rice, wheat, radish, tomato, mungbeanand mustard under control laboratory condition. A control (distilled waterwithout extract) was also maintained in every cases and the bioassayexperiment was replicated thrice. The results of this research showed thatthe shoot and root growth inhibition of rice, wheat, jute, tomato, radish,mungbean and mustard by leaf, bark, stem, twig and root extracts of J.curcus, R. communis and A. polystachya varied significantly. Compareto the shoot growth, the root growth of the test species inhibited moreexcept J. curcus. The leaf and root have higher allelopathic potential thanany other parts of the studied plants. Finally, it can be concluded here thatJ. curcus plant extracts has higher allelopathic potential than other twoplants R. communis and A. polystachya. Therefore, J. curcus can be usedas a candidate plant for isolation and identification of allelopathic substancesfor the development of new natural herbicides.

Changes in particulate and mineral-associated organic carbon with land use in contrasting soils

Soil organic carbon(SOC)is the largest terrestrial carbon(C)stock,and the capacity of soils to preserve organic C(OC)varies with many factors,including land use,soil type,and soil depth.We investigated the effect of land use change on soil particulate organic matter(POM)and mineral-associated organic matter(MOM).Surface(0–10 cm)and subsurface(60–70 cm)samples were collected from paired sites(native and cropped)of four contrasting soils.Bulk soils were separated into POM and MOM fractions,which were analyzed for mineralogy,OC,nitrogen,isotopic signatures,and14C.The POM fractions of surface soils were relatively unaffected by land use change,possibly because of the continuous input of crop residues,whereas the POM fractions in corresponding subsurface soils lost more OC.In surface soils,MOM fractions dominated by the oxides of iron and aluminum(oxide-OM)lost more OC than those dominated by phyllosilicates and quartz,which was attributed to diverse organic matter(OM)input and the extent of OC saturation limit of soils.In contrast,oxide-OM fractions were less affected than the other two MOM fractions in the subsurface soils,possibly due to OC protection via organo-mineral associations.The deviations in isotopic signature(linked with vegetation)across the fractions suggested that fresh crop residues constituted the bulk of OM in surface soils(supported by greater14C).Increased isotopic signatures and lower14C in subsurface MOM fractions suggested the association of more microbially processed,aged OC with oxide-OM fractions than with the other MOM fractions.The results reveal that the quantity and quality of OC after land use change is influenced by the nature of C input in surface soils and by mineral-organic association in subsurface soils.