Net House Conditions Research Articles

Growing Tomato under Protected Cultivation Conditions: Overall Effects on Productivity, Nutritional Yield, and Pest Incidences

Tomato continues to be one of the most important crops worldwide, and protected cultivation is practiced to overcome the biotic and abiotic stresses to which the plant are exposed during growth. In this study we evaluated the effect of colored net houses on the growth, yield and nutritional values, as well as the incidence of common pests under three different light conditions: (1) colored (magenta), (2) conventional (white), and open field conditions. A colored net house led the plants to grow taller with higher lycopene content, but recorded a higher number of whiteflies, compared to the conventional net house and open field conditions. Furthermore, plants under protected structures recorded lower SPAD values, but larger terminal leaflets, lower damage by leaf miners, but more damage caused by spider mites compared to those plants grown under open field conditions. Overall, we found that the use of colored net houses provided a positive effect on tomato production in terms of improvement in morphometric parameters, however, to obtain higher yields under this production system, it is important to reduce the elevated temperature and increase the relative humidity inside the protective structures to be adapted for local growing conditions in Taiwan.

Comparison of DNA Extraction Protocols for Molecular Identification of Root Knot Nematode (<em>Meloidogyne</em> Spp.) Using Egg Masses

There is a dire need of alternative reliable and non-laborious methods with high resolution for identification of the root-knot nematodes at the species level where molecular techniques have shown the potentials. This study assessed four DNA extraction protocols, (<em>i.e</em>. TNES buffer method, Modified CTAB method, Phenol / Chloroform Method and 1% SDS method) to extract DNA from egg masses of root knot nematodes. Egg masses were collected from pure cultures of nematodes maintained in tomato cultivation under net house condition. After extraction of genomic DNA, Polymerase Chain Reaction was performed to determine the success of the method of DNA extraction. The 1% SDS method with incubation at -20 0C for 1hr and incubated at 65 0C for 1 hr and again incubated for 95 0C for 10 min, was a better method to result in intense PCR bands of the expected sizes (720 bp and 999 bp) when amplified by <em>Meloidogyne </em>genus and <em>Meloidogyne incognita </em>specific primers. This DNA extraction procedure could contribute as an effective method to molecular identification of species and other downstream applications of population studies of root knot nematodes.

Effect of different growing environments on growth, yield and quality attributes of strawberry

Shading is one of the cooling methods for changing the microclimate and maximizing crop growth in hot and sunny regions. A study was conducted to determine the effect of the growing environment on the growth, yield and fruit quality parameters of strawberries. The experimental treatments include net house, poly shade house, UV poly shade house, and open field (control) conditions. The results revealed that the plants produced in the net house condition had maximum plant height (18.5 cm), total chlorophyll content (62.66), fruit number (17), and yield (289.16 g/plant) of strawberries. In contrast, plants grown under UV poly shade conditions recorded higher total soluble solid (7 °Brix), titratable acidity (0.46%), ascorbic acid (39.68 mg/100g) and lower pH (3.41). Reducing sugar (7.57 mg/g) and phenol (2.44 mg/g) levels were higher in fruits grown in poly shade. Results indicated that the most suitable growing condition for yield and yield parameters of strawberries is under the net house. In contrast, UV poly and poly house conditions are favourable for producing better quality fruit.

Life cycle and morphometry of Rugose spiraling whitefly, Aleyrodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) on coconut

The present study investigated the biology and morphometric analysis of rugose spiralling whitefly (RSW), Aleyrodicus rugioperculatus on coconut under mini net house condition at Department of Agricultural Entomology, Tamil Nadu Agricultural University-Coimbatore during 2019-2020. The biology of rugose spiralling whitefly was studied by clip cage method and morphometrics were done using Leica image analyser. Total lifecycle of rugose spiraling whitefly was 56.23 ± 2.20 days. Developmental period of egg, nymphal, pupal and adult period was 8.47 ± 0.26, 17.46 ± 0.76, 10.30 ± 0.29 and 20.00 ± 1.00 days, respectively. In morphometrics, Length and width of egg (0.31 ± 0.01 mm and 0.11± 0.02 mm), nymphal (0.94 ± 0.01 mm and 0.82 ± 0.01 mm), pupal (1.23 ± 0.01 mm and 1.00 ± 0.01 mm) was recorded. A nymphal parasitoid, Encarsia guadeloupae can be potential natural enemy for effective management of rugose spiraling whitefly.

Performance of parthenocarpic lines of brinjal (Solanum melongena L.) in net house and open field during the rainy season

Brinjal carries facultative parthenocarpy that is affected byseasonal variation and the environment of cultivation.Twenty-four parthenocarpic genotypes involving threeparthenocarpic hybrid checks and one non-parthenocarpicvarietal check (Punjab Neelam) were included to assess theirperformance under net house and open-field conditionsduring the rainy season. The genotypes, environments, andtheir interactions affected the performance of all the traitsunder investigation. Among the genotypes, PC-104-13-3,PC-104-13-1, PC-104-12-2, PC-104-3-1, PC-133-1, PC-136-4,PC-115-1, and non-parthenocarpic check Punjab Neelam hadbeen the best for vegetative growth, while 93213-PC-2-1and 93213-PC-2-3 for earliness and yield-related traits. Ingeneral, all the vegetative, flowering, fruiting, and yieldrelatedtraits flourished better under net house conditionsas compared to open field conditions. Interaction effectsbetween environment and genotype indicated that 93213-PC-2-1 and 93213-PC-2-3 were earlier for days to first harvest(35.0 and 38.0 days), at the top for the number of flowers percluster (10.67 and 11.33, respectively), the number of fruitsper cluster (6.67 and 7.00, respectively) and the maximumnumber of marketable fruits per plant (25.51 and 28.03,respectively), when grown under net house conditions. Themaximum and statistically at par average fruit weight wasobserved in PC-104-13-1 (298.33 g) and parthenocarpichybrid check Nikki (291.67 g) in net house conditions. Theparthenocarpic genotypes PC-123-1 (2.89 kg), PC-2016-6-2(2.87 kg), PC-1-12-2 (2.78 kg), PC-104-13-1 (2.64 kg), PC-17-1(2.61 kg), parthenocarpic hybrid checks Shelly (2.74 kg) andNikki (2.73 kg), and Amaron check (2.55 kg) displayed at parmarketable fruit yield per plant under net house conditions.In all, the marketable yield and its related traits during therainy season were affected by the environment of cultivation,where the parthenocarpic genotypes performed better innet house conditions in brinjal.

High-Density GBS-Based Genetic Linkage Map Construction and QTL Identification Associated With Yellow Mosaic Disease Resistance in Bitter Gourd (Momordica charantia L.).

Yellow mosaic disease (YMD) in bitter gourd (Momordica charantia) is a devastating disease that seriously affects its yield. Although there is currently no effective method to control the disease, breeding of resistant varieties is the most effective and economic option. Moreover, quantitative trait locus (QTL) associated with resistance to YMD has not yet been reported. With the objective of mapping YMD resistance in bitter gourd, the susceptible parent “Punjab-14” and the resistant parent “PAUBG-6” were crossed to obtain F4 mapping population comprising 101 individuals. In the present study, the genotyping by sequencing (GBS) approach was used to develop the genetic linkage map. The map contained 3,144 single nucleotide polymorphism (SNP) markers, consisted of 15 linkage groups, and it spanned 2415.2 cM with an average marker distance of 0.7 cM. By adopting the artificial and field inoculation techniques, F4:5 individuals were phenotyped for disease resistance in Nethouse (2019), Rainy (2019), and Spring season (2020). The QTL analysis using the genetic map and phenotyping data identified three QTLs qYMD.pau_3.1, qYMD.pau_4.1, and qYMD.pau_5.1 on chromosome 3, 4, and 5 respectively. Among these, qYMD.pau_3.1, qYMD.pau_4.1 QTLs were identified during the rainy season, explaining the 13.5 and 21.6% phenotypic variance respectively, whereas, during the spring season, qYMD.pau_4.1 and qYMD.pau_5.1 QTLs were observed with 17.5 and 22.1% phenotypic variance respectively. Only one QTL qYMD.pau_5.1 was identified for disease resistance under nethouse conditions with 15.6% phenotypic variance. To our knowledge, this is the first report on the identification of QTLs associated with YMD resistance in bitter gourd using SNP markers. The information generated in this study is very useful in the future for fine-mapping and marker-assisted selection for disease resistance.

EVALUATION OF TRICHODERMA HARZIANUM IN CONTROLLING LATE BLIGHT OF POTATO

Evaluation of Trichoderma harzianum in reducing mycelial growth of Phytophthora infestans as well as in controlling late blight of potato was done in Microbiology and Biocontrol laboratory and Net-house, Department of Plant Pathology, Bangladesh Agricultural University, Mymensingh during 2019-2020, Bangladesh. The experiment was conducted using popular potato variety Diamant and native variety Challisha. T. harzianum was evaluated in net-house and in-vitro condition. Fungicide Indofil M-45 (Mancozeb) was used as positive check for comparison. In Net-house experiment, T. harzianum increased plant height, number of tubers and fresh weight of tubers over control treatment for the both of the varieties of potato. T. harzianum on late blight of potato (var. Diamant) showed a significantly better management over control treatment. In comparison to non-treated control treatment, reduced infection of late blight was found in the T.harzianum treated plants, whereas increase disease severity was calculated in control treatment. After harvesting, tuber infection in T. harzianum treated plants was not observed. Percent inhibition of tuber infection over control was 100%. Indofil M-45 suppressed Disease severity but comparatively less effective than T. harzianum in the long run. In case of variety Challisha similar trend of results were observed. In dual culture assay, T. harzianum showed highest inhibitory effect in suppressing mycelial growth of P. infestans. T. harzianum showed 86.67% inhibition of mycelial growth of P. infestans over control. Thus, it can be concluded that T. harzianum is effective to control late blight of potato and sometimes comparable to chemical fungicide in net-house condition.

Glucanolytic rhizobacteria associated with wheat- maize cropping system suppress the Fusarium wilt of tomato (Lycopersicum esculentum L)

Tomato wilt caused by F. oxysporum (Fox) is one of the most destructive diseases, which causes qualitative and quantitative losses. In the present study, the bio-efficacy of glucanolytic bacteria was assessed on tomato against Fusarium wilt under net house conditions. A 178 rhizobacteria were isolated from the wheat-maize cropping system of arid and semi-arid regions. Only ten out of 178 rhizobacteria produced glucanases. The glucanolytic bacteria exhibited variable ability to produce β-1, 3/4-glucanases (0.11 – 0.30 U/mL). The glucanase production was higher at pH 7 (SZ =7.89 mm - 14.11 mm) followed by pH 9 (SZ=5.78 mm - 10.56 mm) and pH 5 (SZ=5.55 mm - 10.00 mm). The glucanolytic bacteria MAZ 10SR, 13, 18, 32, 48, 51, 73, 86, 117, 151 & 165 suppressed F. oxysporum (43–68%) causing tomato wilt and other phytopathogens viz F. moniliforme (44–63%), M. phaseolina (42–65%) and P. oryzae (42–67%). The glucanolytic bacteria also produced different antifungal metabolites/compounds viz siderophores, protease, and lipopeptide antibiotic surfactin. In planta assays indicated the ability of glucanolytic bacteria Bacillus subtilis MAZ 10SR, 51, 117 & 165 to colonize the tomato rhizosphere by 7.4 – 8.9 log CFU/g of soil. They decreased the Fusarium wilt incidence with disease severity of 22–31% as compared to that of control (disease severity = 56%). A significant quantity of glucanases (0.33–0.70 U/mg of soil) was recovered from the tomato rhizosphere inoculated with the effective glucanolytic bacteria. The glucanolytic rhizobacteria were identified as Achromobacter mucicolens, Enterobacter cloacae, Serratia marcescens, and Bacillus spp. by 16S rRNA gene analysis. The utilization of glucanolytic bacteria could be a worthy strategy in the biological control of soil-borne pathogens.

Biological Control of Rice Sheath Blight Disease (Rhizoctonia solani) Using Bio-pesticides and Bio-control Agents

A series of experiments were conducted in Plant Pathology Laboratory at Bangladesh Rice Research Institute (BRRI), Gazipur to know the efficacy of four bio-pesticides Recharge, Microtech1, Agroplus and Chitin and two bio-control agents (Trichoderma harzianum and Bacillus subtilis) on the major rice disease sheath blight (ShB) caused by Rhizoctonia solani in in-vitro and field condition. One fungicide Nativo (Tebuconazole 50% + Trifloxystrobin 25%) and one disease control (without any treatments) were also included as treatment for comparison. Radial mycelia growth of R. solani was mostly inhibited by a Bangladesh Trichoderma harzianum (BT1), Recharge and chemical fungicide Nativo 75 G at 48 hours of dual contact of R. solani and tested bio-pesticides or bio-control agents in in-vitro. The other bio-pesticides along with B. subtilis didn’t show any inhibition effect on the mycelia growth of R. solani which was similar to control (only water) treatment. Fungal inhibition 87.5% and 86.3% of Rhizoctonia solani was obtained by Recharge and Trichoderma harzianum (BT1), respectively which was nearly similar to the chemical treatment Nativo (96.3%) in in-vitro dual culture method compared to control treatment. In net house condition, 74% sheath blight disease was inhibited by soil application of Recharge (0.3 g/m2 with 50 ml water) for two times at the time of transplanting and 30 days after transplanting (DAT), whereas similar soil application of B. subtilis (OD600=0.3) was not found effective to control the ShB disease (&lt; 30% disease reduction). The highest ShB disease was reduced by the chemical control Nativo 75 G (94.2%) followed by BT1 (89%), bio-pesticide Recharge (70.8%), Microtech1 (37.4%) and Chitin (61.3%) compared with the disease control when the tested materials were sprayed for two times (3 days before and 4 days after inoculation).&#x0D; Bangladesh Rice J. 24 (1): 47-58, 2020

Influence of soil solarization on the multiplication of aeroponic seed potato under net house (Gen-0) and open field conditions (Gen-1) of north central India

A field experiment was conducted at ICAR- CPRI, Regional Station, Gwalior, Madhya Pradesh to study the effect of soil solarization on weed population and multiplication of seed potatoes under aphid proof net house (Gen-0) and subsequently under field conditions (Gen-1) of 3 potato cultivars, viz. Kufri Mohan, Kufri Chipsona-1 and Kufri Lauvkar during 2017-18 and 2018-19. Treatments were replicated thrice in split plot design. The experimental area was solarized with black polythene and paddy straw mulch, whereas, unsolarized plots served as control. Mean monthly maximum temperature at all the soil depths was higher in polythene solarized plots followed by unsolarized and paddy straw mulch solarized plots under both net house and open field conditions. Soil nutrient properties, viz. pH, OC, available N, P and K were influenced by soil solarization both at planting and harvesting. Solarization with polythene and paddy straw mulch resulted in 88.23% and 41.05% reduction in weed population under net house and 74.80 and 37.79% reduction under open field conditions. Under net house conditions, total tuber yield was significantly higher with polythene solarization (29.33 t/ha), whereas, under open field conditions yield was maximum with paddy straw mulch (37.45 t/ha) over other two treatments respectively.

Successive double cropping of potato minitubers under insect proof net house for increased seed productivity

Non-availability of disease-free quality seed material is the most important factor affecting low productivity of potato in India. Successive cropping of disease free minitubers under net house conditions, in the north western plains of India, can be an important intervention for utilizing this expensive vector free space and prevailing potato growing climate of the region in the most sustainable way. A field study was undertaken during 2016-18 to evaluate this hypothesis for its productivity and economics over single crop conventionally taken in the region. Minitubers of six potato varieties were grown in single and successive cropping patters under net house in the region. The summed yield attributes of their early (DCE) and late planted (DCL) successive crops were compared to single cropping (SC) on per meter square basis. Corresponding observations on morphological traits and yield attributes were quite encouraging. Minituber yield of under size, seed size and combined was 1.99, 1.88 and 1.98 times higher in double crop as compared to conventional single crop. As a result, cost of production declined (2.52 times) and net profit increased (3.15 times) in double crop. Cost of production per tuber was reduced in this technique from ₹ 2.01-1.28 per minituber. Higher profits and productivity under successive planting are achievable and this innovative technology can be easily adopted by the stakeholders for improving multiplication of early generation planting material, which would translate into availability of increased seed material after stipulated multiplications.

Antinemic activity of ferrocenyl chalcones against Meloidogyne incognita infestation in tomato

A series of ferrocenyl chalcones using acetylferrocene with different aldehydes were synthesized and their in vitro evaluation against Meloidogyne incognita was reported. The present study was carried out in net house conditions, Division of Nematology, ICAR-IARI, during rabi 2018-19, the bioefficacy evaluation of most effective compounds, identified by in vitro results, along with Carbofuran 3G in pot cultured tomato is reported. The identified, five most effective compounds, (2E)-1-Ferrocenyl-3-(4-bromophenyl)-prop-2-en-1-one (3b), (2E)-1-Ferrocenyl-3-(4- methoxyphenyl)-prop-2-en-1-one (3f), (2E)-1-Ferrocenyl-3-(3,4,5-trimethoxyphenyl)-prop-2-en-1-one (3h), (2E)-1- Ferrocenyl-3-(4-nitrophenyl) prop-2-en-1-one (3m) and (2E)-1-Ferrocenyl-3-(2,6-dichlorophenyl)-prop-2-en-1-one (3o) were undertaken for pot experiment at different concentrations, viz. 20, 40 and 80 ppm and by soil drenching and root dipping methods. The study revealed that all plant growth parameters were positively influenced by these compounds. It was also observed that the presence of electron releasing group positively influences the efficacy and the activity was highest in compound 3f and 3h @ 80 ppm at 30 DAI and 60 DAI. The activity was higher in soil drenching compared to root dipping method.

Design and transfer of&lt;i&gt; OsSWEET14&lt;/i&gt;-editing T-DNA construct to bac thom 7 rice cultivar

Bac thom 7 rice (BT7 rice) is one of the major elite rice cultivars in Vietnam with superior productivity and quality but very susceptible to bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae. The gene OsSWEET14, belonging to the OsSWEET family which encodes sugar transport proteins, is considered to be a susceptible gene involved in the virulence of Xoo. At least three cis-elements (EBE - Effector-binding element), including Tal5, PthXo3 and AvrXa7 on BT7 OsSWEET14 promoter, bind specifically to well-known transcription activator–like effectors (TALEs) of many Asian Xoo bacterium strains. In this study, a T-DNA construct which expressed the protein-RNA complex CRISPR/Cas for editing three EBEs position on the OsSWEET14 promoter was designed. The recombinant binary vector was tested by PCR, restriction enzyme and finally sequencing and then successfully transferred to Bac thom 7 rice through Agrobacterium tumefaciens. 28 of 30 hygromycin-resistant regenerated rice lines that grew and developed normally under nethouse conditions were selected by PCR with specific primers. Among these, twelve transgenic rice lines were identified carrying one copy of the T-DNA construct. The presence of CRISPR/Cas9-induced mutations of the targeted promoter in the transgenic plants were confirmed by T7EI assay. These results provide the basis to determine the role of OsSWEET14 in the susceptibility of Bac thom 7 rice to Xanthomonas oryzae pv. oryzae -caused disease, towards the further goal of generating an improved Bac thom 7 rice variety with broad-spectrum bacterial leaf blight resistance using CRISPR/Cas9 technology.

Indigenous Plant Growth Promoting Rhizobacteria and Chemical Fertilizers: Impact on Soil Health and Productivity of Capsicum (Capsicum Annuum L.) in North Western Himalayan Region

ABSTRACT At present, no commercial indigenous plant growth-promoting rhizobacteria (PGPR) is available for Capsicum crop in North-Western Himalayan Region. Therefore, PGPR were isolated from rhizosphere and root samples of capsicum collected from 28 locations of agro-climatic zones I, II and III of Himachal Pradesh. Thirty-four morphological distinct isolates were screened for multifarious plant growth-promoting traits. Four best PGPR isolates (MAT8, KAN11, JHA6 and ROH14) exhibiting maximum increase in capsicum seed germination were further screened at 80, 60 and 40% of recommended chemical doses of nitrogen (75 Kg ha−1) and phosphorus (70 Kg ha−1) fertilizer (RDNP) for capsicum growth and yield under net-house conditions. Two isolates, ROH14 (Bacillus amyloliquefaciens, Accession number KX447671) and JHA6 (Pseudomonas aeruginosa, Accession number KX447673), alone and in consortia along with 60 and 80% RDNP were further selected for two-year field experimentation. The conjoint application of PGPR isolate (JHA6 and ROH14) along with 80% RDNP brought a significant increase in yield (25.9%), plant height (8.2%), biomass (9.4%), nitrogen (47.1%) and phosphorus uptake (34.0%) over 100% of recommended doses of chemical fertilizers. In addition, the treatment also resulted in enhanced soil properties in terms of available contents of nitrogen and phosphorus, enzymatic activities (dehydrogenase, phosphatase and phytase), microbial population and microbial biomass-carbon besides providing net return of Rs 4484170. The study, therefore, indicates the potential of Bacillus amyloliquefaciens (ROH14) and Pseudomonas aeruginosa (JHA6) in partial replacement of nitrogen and phosphorus (~20%) applied through chemical fertilizers, providing Benefit/Cost ratio 2.73 along with sustainable crop production.

Estimation of Yield Loss of Cowpea, [Vigna unguiculata (L.) Walp.] with Reaction Response of Few Genotypes against Root Knot Nematode, Meloidogyne incognita (Kofoid and White), Chitwood

Background: Root knot nematode, Meloidogyne incognita is one of the main biotic constraints in reducing the quantity and quality of the cowpea crop in most of the growing areas of the world. The nematode produces galls on roots and disrupt the physiology of the plant by reducing crop yield and product quality and are therefore of great economic importance.Methods: Studies were conducted to estimate the yield loss of cowpea in field condition along with evaluation of few genotypes under net house condition against root knot nematode based on gall index, reaction response and number of egg masses/ 5 g of root at Directorate of Research, BCKV, West Bengal. Estimation of cowpea yield loss was conducted with the parameter of mean yield, percentage avoidable and increase in yield, Root Knot Index (RKI in 1-5 scale) and final nematode population reduction. Result: Under treated condition, cowpea yield was significantly increased ranging from 10.93 to 14.58% with 37.19 to 38.17% reduction of nematode population. The range of avoidable yield loss was 9.85 to 12.72%. In response reaction, 28 genotypes were found as moderately resistant. Local cowpea cultivar, Kashikanchan may be avoided at nematode infection area due to its high susceptibility and the moderately resistant genotypes may be suggested for the use in future breeding studies as a parental material to develop the root knot nematode resistant cultivars.

Screening drought tolerance of Vietnamese rice landraces in the laboratory and net house conditions

Screening drought tolerance of Vietnamese rice landraces in the laboratory and net house conditions

Effect of different growing environments on growth, yield and quality attributes of strawberry

Shading is one of the cooling methods for changing the microclimate and maximizing crop growth in hot and sunny regions. A study was conducted to determine the effect of the growing environment on the growth, yield and fruit quality parameters of strawberries. The experimental treatments include net house, poly shade house, UV poly shade house, and open field (control) conditions. The results revealed that the plants produced in the net house condition had maximum plant height (18.5 cm), total chlorophyll content (62.66), fruit number (17), and yield (289.16 g/plant) of strawberries. In contrast, plants grown under UV poly shade conditions recorded higher total soluble solid (7 °Brix), titratable acidity (0.46%), ascorbic acid (39.68 mg/100g) and lower pH (3.41). Reducing sugar (7.57 mg/g) and phenol (2.44 mg/g) levels were higher in fruits grown in poly shade. Results indicated that the most suitable growing condition for yield and yield parameters of strawberries is under the net house. In contrast, UV poly and poly house conditions are favourable for producing better quality fruit.

Microsatellite diversity analysis and QTL identification among progenies derived from aerobic × basmati rice (Oryza sativa) cross under direct-seeded conditions

The present investigation was designed to identify QTL associated with various traits under aerobic condition using F3 and F4 population derived from the cross MASARB25 (aerobic rice) and IB370 (basmati rice). The phenotyping was done in both field and net house conditions during the kharif seasons of 2013-14 and 2014-15. The result indicated high variation among the population for studied traits and parabolic frequency distribution was recorded for panicle length, effective number of tillers/plant, 1000-grain weight while, for grain length/breadth ratio and root thickness, frequency distribution curve were skewed toward MASARB25. Composite interval mapping identified total 16 QTLs on chromosomes 1, 2, 3, 4, 6, 9, 10 and 12 during both the years. Maximum QTL were detected for grain lengthbreadth ratio. LOD score of these QTLs ranged from 2.88 (qENT12.1) to 5.51 (qLB3.1) and explained 61.63% and 69.04% variance, respectively. The QTL mapped for grain yield/plant (qGYP6.1) on chromosome 6 had LOD score of 2.90 and explained 28.4% phenotypic variation. The identified QTL in present investigation showed high phenotypic variation, hence after validation these QTLs could be used for the improvement of rice under aerobic condition.

Efficiency of using organic fertilizer from seafood sludge as substrate and hydroponic solution on leafy vegetable yield

The aim of this study was to use organic fertilizer from seafood sludge as substrate and as hydroponic solution. The first experiment was carried out with 4 treatments in net house condition including: (1) control (only soil), (2) Soil+ recommended chemical fertilizer, (3) Soil + 5 tons/ha seafood sludge compost (SSC), and (4) Soil + 5 tons/ha sugarcane cake compost (SCC). The second experiment was conducted with 4 treatments consisting of (1) water (control), (2) extracted solution at ratio of 1:5, (3) extracted solution at ratio of 1:10, and (4) commercial hydroponic solution. Results showed that the yield of green mustard was found in the treatment amended with 5 tons/ha of SS compost five times higher than control treatment. The yield of salad vegetable on hydroponic solution at diluted ratio of 1:10 increased more than 65% compared to the control treatment.

A RESPONSE OF SOME JUTE (CORCHORUS SPP.) ACCESSIONS TO JUTE YELLOW MITE, POLYPHAGOTARSONEMOUS LATUS BANKS UNDER NATURAL CONDITION

The jute yellow mite Polyphagotarsonemus latus constitutes one of the major pests of jute crop in Bangladesh. The objective of this work was to find out the sources of resistance/tolerance accessions against jute yellow mite. This experiment was carried out in the fields of Bangladesh Agricultural University, Mymensingh, JAES, Manikganj and the Central station, BJRI, Dhaka, during jute growing seasons 2011 and 2012. Out of 79 accessions, only 13 accessions were found less susceptible to yellow mite. These accessions were studied further in the field and net-house condition. Considering the level of infestation in the net-house condition only three accessions namely 1510, 890 and 33-1-244 (A) 2 were found to perform better showing 9.75, 9.68 and 9.93% infestation. In field condition, in case of olitorius, accession 1510 showed lowest infestations (9.90%) giving maximum plant height 324.15 cm and yield 3.26 ton/ha. In case of capsularis, accession 890 also resulted minimum infestation (10.23%) giving satisfactory plant height 315.27 cm and yield 3.14 ton/ha respectively. Accessions 1510, 890 and 33-1-244 (A) 2 could be recommended as breeding materials for evolving yellow mite resistant jute variety.