Maximum Leaf Area Research Articles

Modeling realized gains in Douglas-fir (Pseudotsuga menziesii) using laser scanning data from unmanned aircraft systems (UAS)

Tree breeding programs form an integral part of sustainable forest management by providing genetically improved stock for reforestation. These programs rely on accurate phenotyping of forest trials, which become increasingly difficult to assess as trees grow larger and canopy closure occurs. Airborne laser scanning (ALS) provides three-dimensional point cloud information on forest structure which can be used to characterize phenotypes of forest trees. We analyzed 22-year-old realized gain trials of coastal Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco var. menziesii) at three sites in coastal British Columbia, Canada, using dense point clouds produced from ALS acquired by unmanned aircraft system (UAS). We assessed the accuracy of ALS data against ground estimates of stand maximum height (r2 = 0.90, p < 0.001) and leaf area (r2 = 0.82, p < 0.001). We characterized phenotypes in blocks of differing levels of predicted genetic gain by generating a suite of quantitative point cloud metrics to describe four categories of stand attributes: Height, Density, Heterogeneity, and Volume. By normalizing all metrics to percent change from the means of unimproved control blocks, we analyzed point cloud metrics in terms of realized gains comparable across sites. Variable importance scores derived from conditional Random Forests indicated that descriptors of canopy height were the most important predictors of genetic gain for volume-per-ha. We selected a simple bivariate regression model using gains in mean canopy height and effective leaf area index to predict realized genetic gain for total stand volume (R2 = 0.82 – 0.94, p < 0.01, RMSE = 9.12 – 10.8%). Based on the consistent performance of this model across sites, we suggest that characterizing genetic trials in terms of increases in tree height and leaf area is a robust approach to predicting volume gains in this system. Additionally, we discuss the application of ALS as part of a phenotyping platform to inform operational decision making and forestry policy in British Columbia.

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Among the significant number of grain cereals used for the production of solid kinds of biofuels in the form of fuel pellets and briquettes as the acceptable raw material is biomass of switch grass, or “virgate millet”. The main purpose of the research was to substantiate a new approach for determination of the optimal seeding rate and calculation of the yield of biomass of switch grass by means of application of morphometric indices of leaf surface area and mass of the aboveground part, determining the statistical relationships between them. It is determined that the leaf surface area and the mass of the aboveground part of the switch grass consist of the sum of the plant area; mathematical calculations based on correlations were used to obtain it. The correlation coefficient between the surface area of the leaves on the shoot and its height is calculated. The maximum leaf area of virgate millet plants can be achieved at a seeding rate of 4.0–4.5 million seeds/ha, which makes it possible to form in the first year of vegetation 70–80 plants per linear meter. The height of the stem and the number of leaves on it has the greatest influence on the leaf surface area and the mass of stems of switch grass plants. The close multiple correlations between the leaf surface area and the mass of the stem and its height and the number of leaves on it make it possible to calculate the leaf surface area and stem mass based on morphometric indices of switch grass plants. The results of determination of the indices of yield formation of switch grass depending on the morphometric data of the leaf surface area and the mass of the ground shoot are presented.

Flumetralin and dimethyl piperidinium chloride alter light distribution in cotton canopies by optimizing the spatial configuration of leaves and bolls

Plant growth regulators (PGRs) are frequently used to adjust cotton growth and development. The objectives of this study were to determine how PGRs affect plant morphology, light distribution and the spatial distribution of leaves and bolls within the cotton canopy. The field experiments were carried out at Shihezi (Xinjiang Uyghur Autonomous Region, China) in 2014 and 2015. The experiment included two PGR treatments: (i) flumetralin (active ingredient (a.i.), N-N-ethyl-2,6-dinitro-4-aniline) and (ii) mepiquat chloride (a.i., 1-dimethyl-piperidiniuchloride) plus flumetralin. No PGR (manual topping) was applied in the control treatment. The chemically-topped plants were taller and had more main stem internodes than the manually-topped plants. Furthermore, the PGRs significantly reduced the length of fruiting branches in the upper canopy, resulting in a more compact canopy. The maximum leaf area index was significantly greater in the chemically-topped treatments than that in the control. In particular, the PGRs increased leaf area index by 25% in the upper canopy. The leaf area duration was also longer in the chemically-topped treatments than in the control. Compared with the control, the chemically-topped treatments increased canopy diffuse non-interceptance by 35.75% in the upper canopy layer, while reducing the fraction of intercepted photosynthetically active radiation by 14.45% in the upper canopy layer. Light transmittance in the upper and middle canopy layers was greater in the chemically-topped treatments than in the control, which increased boll numbers in both the upper canopy and the middle canopy. However, the chemically-topped treatments resulted in less light-leakage through the lower canopy layer during the late growth stages, which had a tendency to increase boll numbers in the whole canopy. In summary, the PGRs optimized canopy shape, light distribution and the spatial distribution of bolls and leaves.

Response of Different Plant Growth Regulators on Fruit Yield of Brinjal

The experiment was conducted at Instructional cum Research Farm, Department of Horticulture, Biswanath College of Agriculture (AAU) Biswanath Chariali, Sonitpur district of Assam during 2014-15 in order to study the response of plant growth regulators on physiogical and fruit yield of brinjal (Solanum melongena L.) cv. JC -1. The experiment was laid out in a Randomized Block Design with ten treatments replicated three times. The details of treatment comprised of GA3 (25, 50 and 100 ppm), IAA (25, 50 and 100 ppm), NAA (25, 50 and 100 ppm) and control (distilled water). During the period of investigation the growth regulators showed significant response on physiological and yield attributing characters of brinjal. The result revealed that the maximum leaf area index (2.82) was recorded under GA3 at100 ppm (T3) while GA3 at 50 ppm (T2) recorded the highest (802.40 g) total dry weight per plant at harvest. However, the highest leaf chlorophyll content index (44.50) was recorded under treatment with NAA at 50 ppm (T8). Foliar application GA3 at 50 ppm (T2) exhibited significantly higher total number of flower per plant (38.49), number of fruit per plant (18.56) and fruit yield (1.58 kg plant−1 and 377.00 q ha−1). It may be concluded from the experiments that GA3 proved to be the best in improving the physiological and yield attributing parameters in brinjal.

Modelling the hydrologic effects of vegetation growth on the long-term trajectory of a reclamation watershed

Reclamation watersheds that integrate fen peatlands into the design require the inclusion of uplands that are capable of supporting forest development while concurrently supplying sufficient groundwater recharge to downgradient wetland ecosystems. This necessitates selecting materials with suitable soil hydraulic properties and identifying the appropriate thickness and layering to fulfill the dual function of uplands as water storage, and water conveyance features. Currently, these systems incorporate tailings sand - a mine waste material - overlain by a cover soil of fine forest-floor material. The developmental pathway of these uplands is currently unknown, and it is unclear whether these landforms will provide enough groundwater recharge once a climax vegetation community establishes. Therefore, this research attempts to estimate the maximum density of vegetation, and associated water balance fluxes of a constructed upland integrated into a peatland watershed. The numerical modelling software HYDRUS-1D simulated soil moisture dynamics using a 65-year meteorological record, and a plant water stress algorithm was used to estimate the maximum sustainable leaf area index that the upland could support. Based on the thickness of the cover soil, the upland could support an average leaf area index of 1.2. Under this vegetation density, average annual groundwater recharge was 83 mm, and predominantly supplied by snowmelt (64%). Given this quantity of recharge, the model indicates that the upland will continue to provide enough groundwater to offset the anticipated water deficit in the downgradient fen ecosystem. However, by altering the design of the upland, specifically the spatial arrangement and thickness of cover soil, the same recharge could be supplied while also allowing for a higher average vegetation density. Such a design could allow for the creation of watersheds with a higher proportion of peatland.

Eight years of variations in ecosystem respiration over a residue-incorporated rotation cropland and its controlling factors

The carbon dioxide emissions from cropland play important roles in the regional carbon budget. In this study, continuous measurements of the ecosystem respiration (RE) were obtained using the eddy covariance technique in a winter wheat–summer maize double cropping agroecosystem mainly between 2004 and 2012 in order to identify the among-year variations in RE and the related factors responsible. The annual RE, estimated by Lloyd and Taylor model, which was the most accurate, was 1866.4 ± 105.75 g C m−2 year−1 and it ranged from 1650.68 g C m−2 year−1 to 1945.57 g C m−2 year−1 during the eight years. The seasonal RE values were 867.98 ± 125.24 g C m−2 year−1 and 890.55 ± 131.34 g C m−2 year−1 for wheat and maize, respectively. Additionally, crop residue carbon ranged from 322.73 g C m−2 year−1 in 2012 and 453.49 g C m−2 year−1 in 2007. Correlation analysis indicated that the interannual variations in wheat and maize RE were correlated with the seasonal mean soil water content (W-Ws) and maximum leaf area index (W-LAImax) of wheat, and seasonal mean air temperature of maize (S-Ta), respectively. A rest method was attempted to investigate whether these relationships were occasional or inevitable. The rests of RE, i.e. the difference between simulated and observed RE values, were significantly influenced by LAI of wheat and hourly Ta of maize season but not by hourly Ws of maize season, indicating that the influence of W-LAImax and S-Ta on RE were inevitable outcomes and that of W-Ws on wheat RE was occasional. So we suggested that one should not confirm the controlling factors of interannual variations in carbon fluxes just from simple relationships, which may be statistical coincidences and do not correlated with biotical processes.

Effect of plant bio-regulators on vegetative growth and flowering of gerbera (Gerbera jamesonii B.) cv. Goliath in open field condition

The present investigation entitled “Impact of Plant Bio-regulator on growth and flowering of gerbera (Gerbera jamesonii B.) cv. Goliath” was carried out in premises of Bio-technology cum Tissue Culture Centre, Odisha University of Agriculture and Technology, Bhubaneswar during 2015-16 and 2016-17. The objective of the study was to standardize suitable bio-regulators on flower production in gerbera in open field condition. Apart from control eight treatments of growth regulators were used like GA3 @ 100 ppm, and 150 ppm; Cycocel @ 700 ppm and 800 ppm with or without amino acids as foliar spray. Among vegetative parameters maximum plant spread, leaf length, petiole length, leaf width and leaf area was found in GA3 @ 150 ppm + Amino Acid while maximum leaf number/plant, number of suckers/plant and chlorophyll content in leaf was found in treatment with cycocel @ 700 ppm+ Amino acid. In flowering parameters maximum number of flowers/plant/m2 in a year was found in treatment with cycocel @ 700 ppm + Amino acid.

Growth, yield, physiological and biochemical traits of different accessions of bird of paradise (Strelitzia reginae L.)

Twenty one accessions of bird of paradise (Strelitzia reginae L.) were characterized for various traits at ICAR-IIHR, Bengaluru, India during 2011−2017. Among different accessions, there were significant differences in number fans and leaves, leaf area, leaf biomass, spike yield and vase life. Maximum number of fans were recorded in IC-0624431 and lowest in IC-0624411. The IC-0624427 accession recorded maximum leaf area (311.92 cm2 leaf−1). Cumulative spike yield was significantly higher in IC-0624431 (153 spikes) followed by IC-0624412 (131.0 spikes). There was significant variability in plant height and leaf characteristics such as petiole length, leaf length, and lamina length/breadth. Maximum vase life of 10 days was registered with IC-0624427. Spike length (cm) was maximum in IC-0624433 (149.13) followed by IC-0624419 (130.12). The genotype IC-0624433 recorded higher inflorescence stalk length (128.66 cm) followed by IC-0624419 (108.44 cm) with lowest stalk length of 56.32 cm in IC-0624420. The variation among genotypes for wax content was significant and the wax content was significantly higher in IC-0624433 (0.62 mg cm−2). Anthocyanin content varied from 40. 9 to 12 4.0 mg. Genotype IC-0624419 recorded maximum anthocyanin content of 124.65 mg that was on par with IC-0624433 (122.25 mg). The maximum quantity of carotenoid in florets was recorded in IC-0624410 (22.31 mg) followed by IC-0624430 (19.06 mg). Total annual maintenance cost was estimated at Rs. 96,200 per hectare. IC-0624431 registered maximum net returns of 5.61 per rupee investment followed by IC-0624434 (4.71), IC-0624410 (3.80), IC-0624416 (3.69) and IC-0624414 (3.59). Overall, the accession IC-0624431 of bird of paradise registered better traits in all aspects. Bird of Paradise has low input requirement with less pest and disease load and is economical.

Winter wheat growth and water use under different micro-sprinkling irrigation regimes in the North China Plain

To develop more efficient irrigation technologies and a reasonable and convenient irrigation scheduling for winter wheat production in the North China Plain (NCP), a field experiment with five soil matric potential (SMP) treatments under irrigation with micro-sprinkling hoses was conducted in 2013–2014 and 2014–2015. The SMP thresholds were − 10, − 20, − 30, − 40 and − 50 kPa and monitored using tensiometers at 0.2 m depth and 1.2 m (horizontal distance) from the micro-sprinkling hose. The results indicated that soil moisture consumption occurred mainly in the 0–80 cm soil layer during the anthesis and grain filling stages. The different SMP values had no significant effects on winter wheat plant height, maximum leaf area index, dry biomass, grain yield and yield components and water productivity (WP), but there was a tendency for all these indicators to reach their highest value when the SMP value was around − 40 kPa. Compared with the average winter wheat yield, irrigation amount and WP from local surface irrigation, the − 40 kPa SMP threshold treatment resulted in a yield increase of 10.7%, water savings of 46.5% and WP increase of 5.7%. In the NCP, the SMP threshold of − 40 kPa is recommended to schedule micro-sprinkling irrigation for winter wheat.

Вплив густоти рослин і доз добрив на фотосинтетичну діяль­ність і врожайність сої середньостиглого сорту Святогор в умовах зрошення

Goal. To establish the optimal parameters of photosynthetic activity of crops of mid-season soybean variety Sviatogor in conditions of irrigation in the South of Ukraine depending on plant density and doses of nitrogen fertilizers. Methods. The field — for determination of yield; calculation — for optimization of doses of mineral fertilizers, plant density; measurement-weighe — for fixation of plant height, leaf area, and photosynthetic indices. Results. The density of sowing significantly influenced the leaf area of soybean plants, its indices varied in the range of 23.5–47.38 thousand m2/ha at the density of 300 thousand plants/ha; 26.19–52.42 thousand m2/ha at the density of 600 thousand plants/ha; 50.56–49.92 thousand m2/ha at the density of 900 thousand plants/ha. It was fixed that the leaf area of plants in the plots with the introduction of N30 and N60 was 50% and 49% more than in the variant without fertilizers. High yield was provided by the density of plants 600 t/ha on the background of fertilizers N30 and N60. Conclusions. For the first time for the South of Ukraine, features are determined of the formation of the photosynthetic activity of soybean crops of mid-season variety Sviatohor depending on plant density and doses of nitrogen fertilizers, providing the yield at the level of 4.32–4,47 t/ha. The best performance of interfacial photosynthetic capacity (beginning of flowering — beginning of seed ripening) — 1.38–1.23 million m2 of days/ha, and over the vegetation period — 3.45–3.19 million m2 of days/ha were formed in areas where the plant density was 600 thousand plants/ha on the background of N30 and N60 respectively. Correlation is determined between the yield level and the studied factors. It is found that the maximum leaf area in the ripening phase of the seeds is 52.42 thousand m2/ha at a plant density of 600 thousand plants/ha, and the rate application of nitrogen fertilizer involves a dose of N30.

Effects of nitrogen application rate on the growth traits in seedlings of different quinoa cultivars

Effects of five different nitrogen application rates (i.e., N0, 0 g·kg-1; N1, 0.05 g·kg-1; N2, 0.1 g·kg-1; N3, 0.15 g·kg-1; N4, 0.2 g·kg-1) on the growth of seedlings of eight different quinoa cultivars were investigated in a pot experiment. The results showed that: 1) Across different nitrogen application rates, cultivar GB22 and OY had the highest biomass, but cultivar B2 had the lowest value. The highest flower mass ratio, stem mass ratio, root mass ratio, and leaf mass ratio were found in cultivar B2, GB22, R1, and W23, respectively. 2) The rate of nitrogen application significantly affected seedling growth. Compared with the control (N0), the maximum net photosynthetic rate and biomass accumulation were significantly higher in the lower nitrogen applications (i.e., N1 and N2 treatments), but were lower in the higher nitrogen applications (i.e., N3 and N4 treatments). The significant interactions between cultivar and nitrogen application rate on plant biomass indicated that different quinoa cultivars responded differently to nitrogen rate. The optimum nitrogen application rate (Nopt) required for cultivar R1, MY11, GB22 and OY was 0.05 g·kg-1; while that of cultivar GB11, DB, and B2 was 0.1 g·kg-1; but for cultivar W23, Nopt was less than 0.05 g·kg-1. 3) The interactions between cultivar and nitrogen application rate significantly affected biomass allocation. Below the highest nitrogen rate used (i.e., less than 0.2 g·kg-1), the flower and leaf biomass allocation increased with the increasing nitrogen rates. 4) Across different cultivars and nitrogen application rates, plant biomass was positively correlated to the maximum net photosynthetic rate, plant height, ground diameter, and specific leaf area, respectively. These results provided valuable information for the nutrition management of different quinoa cultivars.

Green leafy mustard: A healthy alternative

Peppery, crispy mustard greens are indeed one of the most nutritious green leafy vegetable available during the winter season. The mustard greens similar to spinach and fenugreek are the storehouse of the number of phytonutrients and have health promotional and disease prevention properties. Five selections from germplasm lines from Uttarakhand hills were evaluated for leaf traits, micronutrient profile and anti-oxidative properties. These lines were very tall, late maturing and slow-growing. The maximum leaf area was found in EEC-1 (590.42 cm2) by virtue of its broadleaf (21.89cm) with high protein (26.68%) and zinc content (2.73mg). EEC-5 showed the highest fresh leaf weight (66.53g) and maximum content of iron (20.23mg). With maximum leaf length (40.72cm), EEC-4 was identified as an excellent source of â-carotene (6480µg) which is precursor of vitamin A. Leafy mustard selection EEC-3 possessed the highest amount of micronutrients like phosphorous (720mg), calcium (240mg) and manganese (6.49mg). Fresh mustard greens were found to be an excellent source of antioxidant like flavonoids (EEC-4, 4.88mg) and also show very high total antioxidative activity (EEC-5, 20.09mg). Therefore, from the above investigation, it was found that green mustard leaves can serve as a healthy alternative to most of the winter season leafy vegetables with their high nutraceutical and disease defensive role.

IMPACT OF FOLIAR APPLICATION OF POTASSIUM SULPHATE ON WEED DYNAMICS AND SOME PHYSIOLOGICAL ATTRIBUTES OF RAINFED BREAD WHEAT

An experiment to find out the wheat growth as affected by foliar application of potassium Sulphate (K2SO4) on different growth stages under rainfed conditions was conducted at the Agricultural Research Institute, Dera Ismail Khan, Pakistan. Potassium doses viz. 0, 12, 18, 24, 30 and 60 kg ha-1 were applied in foliar form at tillering, booting and heading stages of wheat. The course of study revealed that foliar application of K2O in booting stage produced maximum leaf area index (LAI), leaf area duration (LAD), crop growth rate (CGR), net photosynthesis rate (NPR) and grain yield, while its application at heading stage produced maximum net assimilation rate (NAR). Among different doses, the application of potassium at the rate of 60 kg ha-1 potassium at the rate of 60 kg ha-1 produced maximum growth and yield and its components during two consecutive cropping seasons of wheat crop while weed density (m-2), relative weed density (%), fresh weed biomass (g m-2) and dry weed biomass (g m-2) influenced non-significantly for both the years. These findings suggest that foliar application of potassium sulphate @ 60 kg ha-1 along with recommended dose of nitrogen (120 kg ha-1) and phosphorus (90 kg ha-1) is the most suitable for successful wheat production under rainfed conditions.

Impact of parameter uncertainty and water stress parameterization on wheat growth simulations using CERES-Wheat with GLUE

This study used the Crop Environment Resource Synthesis (CERES)-Wheat model to explore the impact of parameter uncertainty and model structure on model output. We obtained observational and management data for winter wheat growth from an experiment conducted in Yangling, China, over 2012/13 and 2013/14, which we used for model input and evaluation. This experiment was conducted with full irrigation to avoid the effect of water stress on winter wheat growth. The Generalized Likelihood Uncertainty Estimation (GLUE) was used to generate 10,000 random parameter sets, including one calibrated parameter set, to explore the effects of parameter uncertainty on model output. Our results showed that GLUE-calibrated parameters were significantly different from observations. Further analysis indicated that frequent water stress occurred in the modeling results, even though no water stress actually occurred with full irrigation. This disagreement resulted mainly from the unrealistic water stress parameterization. GLUE-calibrated parameters matched very well with observations when this parameterization was closed in the CERES-Wheat model. Thus, the unrealistic water stress parameterization strongly affected the GLUE algorithm in locating calibrated parameters. The parameter sensitivity analysis demonstrated that the model errors produced by the water stress parameterization were compensated mainly by the parameters most sensitive to the winter wheat growth and yield simulations, such as the standard kernel weight and phyllochron. Hence, special attention should be paid to these parameters to identify possible structural defects in the model. In addition, results of the parameter uncertainty effect on model output showed that phenology-related simulations could better capture observations when multiple sets of parameters were used with and without water stress conditions. For the yield, maximum leaf area index, and final aboveground biomass, the model generally produced smaller biases without water stress than with water stress due to the unrealistic water stress parameterization. This study provides a better way for improving crop simulations and predictions.

Quantification of light interception within image-based 3-D reconstruction of sole and intercropped canopies over the entire growth season.

Light interception is closely related to canopy architecture. Few studies based on multi-view photography have been conducted in a field environment, particularly studies that link 3-D plant architecture with a radiation model to quantify the dynamic canopy light interception. In this study, we combined realistic 3-D plant architecture with a radiation model to quantify and evaluate the effect of differences in planting patterns and row orientations on canopy light interception. The 3-D architectures of maize and soybean plants were reconstructed for sole crops and intercrops based on multi-view images obtained at five growth dates in the field. We evaluated the accuracy of the calculated leaf length, maximum leaf width, plant height and leaf area according to the measured data. The light distribution within the 3-D plant canopy was calculated with a 3-D radiation model. Finally, we evaluated canopy light interception in different row orientations. There was good agreement between the measured and calculated phenotypic traits, with an R2 >0.97. The light distribution was more uniform for intercropped maize and more concentrated for sole maize. At the maize silking stage, 85 % of radiation was intercepted by approx. 55 % of the upper canopy region for maize and by approx. 33 % of the upper canopy region for soybean. There was no significant difference in daily light interception between the different row orientations for the entire intercropping and sole systems. However, for intercropped maize, near east-west orientations showed approx. 19 % higher daily light interception than near south-north orientations. For intercropped soybean, daily light interception showed the opposite trend. It was approx. 49 % higher for near south-north orientations than for near east-west orientations. The accurate reconstruction of 3-D plants grown in the field based on multi-view images provides the possibility for high-throughput 3-D phenotyping in the field and allows a better understanding of the relationship between canopy architecture and the light environment.

Effective Amendments on Cadmium, Arsenic, Chromium and Lead Contaminated Paddy Soil for Rice Safety

Contamination of paddy soils with heavy metals and metalloids poses a risk to human health through the food chain. For safe agricultural production in contaminated paddy soils, “in situ” remediation through the unavailability of heavy metals from contaminated soils was investigated in order to develop cost-effective and eco-friendly approaches for soils contaminated with complexed heavy metals (HMs) and metalloids. In the present study, the effectiveness of different soil amendments, including sulfur-containing materials (hair or cysteine), manganese compounds as an antagonist and an oxidant, zeolite and iron oxide as adsorbents, and their combinations through coating or modification, was investigated by a pot experiment with rice plants and chemical analysis. Two levels of each treatment were made, termed X1 and X2, which were a single and double dose of each treatment respectively, while CaCO3 was used as a basal and pH enhancement amendment in all treatments to identify the best combination of the above treatments in the in situ remediation of heavy metals and metalloids. The rice plants were kept under the flooded condition. Results indicated that the bioavailability of As, Cd, Cr, and Pb in soil was significantly decreased with level two (X2) of iron oxide coated with modified hairs (T7X2) followed by level two (X2) of zeolite coated with KMnO4. The iron oxide coated with modified hairs (X2) decreased the concentrations of heavy metals and metalloids in rice plants in the order Pb ˃ As ˃ Cr ˃ Cd by 81%, 80%, 79% and 46%, respectively, followed by zeolite coated with KMnO4 (X2) in the order Pb ˃ As ˃ Cr ˃ Cd by 78%, 76%, 71%, and 31%, respectively, to control. The available content of these elements in soil was decreased in the order As &gt; Cr&gt; Pb &gt; Cd by 67%, 66%, 64% and 60%, respectively, through iron oxide coated with modified hairs, followed by zeolite coated with KMnO4 in the order Pb ˃ Cr ˃ Cd ˃ As by 57%, 53%, 50%, and 46%, respectively, to control, which can explain the decreased bioavailability by these amendments. In addition, the maximum shoot dry and leaf area were noticed in the pots treated with iron oxide coated with modified hairs and zeolite coated with KMnO4. There is potential to use modified hairs (MHs) with iron oxide and KMnO4-coated zeolite as soil amendments to develop a cost-effective and efficient “in situ” remediation technology for As, Cd, Pb, and Cr-contaminated rice paddy soils, especially for the soils with complex contamination by Cd and As.

Importance of genetic parameters and uncertainty of MANIHOT, a new mechanistic cassava simulation model.

We identified the most sensitive genotype-specific parameters (GSPs) and their contribution to the uncertainty of the MANIHOT simulation model. We applied a global sensitivity and uncertainty analysis (GSUA) of the GSPs to the simulation outputs for the cassava development, growth, and yield in contrasting environments. We compared enhanced Sampling for Uniformity, a qualitative screening method new to crop simulation modeling, and Sobol, a quantitative, variance-based method. About 80% of the GSPs contributed to most of the variation in maximum leaf area index (LAI), yield, and aboveground biomass at harvest. Relative importance of the GSPs varied between warm and cool temperatures but did not differ between rainfed and no water limitation conditions. Interactions between GSPs explained 20% of the variance in simulated outputs. Overall, the most important GSPs were individual node weight, radiation use efficiency, and maximum individual leaf area. Base temperature for leaf development was more important for cool compared to warm temperatures. Parameter uncertainty had a substantial impact on model predictions in MANIHOT simulations, with the uncertainty 2-5 times larger for warm compared to cool temperatures. Identification of important GSPs provides an objective way to determine the processes of a simulation model that are critical versus those that have little relevance.

Sea level rise impact on mangrove growth and development in Coral Triangle Ecoregion Southeast, Indonesia

The mangroves are among the most at-risk coastal ecosystems, which are especially vulnerable to sea-level rise. This study aimed to know the growth capacity and biochemical defense of mangrove seedlings of Rhizophora mucronata under different sea water logging at experimental condition in Kendari bay, Southeast Sulawesi, Indonesia. Results showed that maximum leaf area, intrinsic rate increase of leaf area and relative growth rate (RGR) of height of the R. mucronata seedlings were significantly higher at treatment of 45 cm from the ground than other treatments, whereas RGR of diameter was the higher at treatment of 30 cm from the ground. Meanwhile, half expansion period leaf area was almost similar for all treatment. However, the carbon and nitrogen ratio in leaves of R. mucronata seedlings was significantly higher at seawater logging of 0 cm from the ground. The flavonoid and vitamin C concentrations in R. mucronata seedlings were higher at higher level inundation indicating protective role of these compounds under seawater logging stress.

Effect of foliar application of acetyl salicylic acid, ascorbic acid and riboflavin on growth, yield and yield component of French bean (Phaseolus vulgaris L Cv. Arka Arjun)

The present experiment was carried out toassess the influence of foliar application of antioxidants on growth, yield and yield component of French bean cv. Arka Arjun. This experiment consisted of 7 treatment viz. Distilled water spray (T1), Acetyl Salicylic Acid @ 100ppm (T2), Acetyl Salicylic Acid @ 200 ppm (T3), Ascorbic Acid @ 100 ppm (T4), Ascorbic Acid @ 200ppm (T5), Riboflavin @ 200 ppm (T6) and Riboflavin @ 400 ppm (T7). Five plants in each plot were randomly selected for recording the growth, yield observation and its parameters. Data was collected on different traits such as Plant height, Number of branches per plant, Number of leaves per plant, Leaf Area Index, Number of pods per plant, Pod weight of ten fruits, Pod length, Pod diameter, Pod yield per plant, Protein content of pod. The salient findings of the present investigation have been summarized as under: such as Plant height was significantly influenced by various treatments The maximum Plant height was recorded in the treatment T5 (Ascorbic Acid @ 200ppm). Maximum number of branches per plant was observed for treatment T5 (Ascorbic Acid @ 200ppm). The maximum number of leaves per plant was recorded in the treatment T5 (Ascorbic Acid @ 200ppm). Maximum Leaf Area Index was recorded in the treatment T5 (Ascorbic Acid @ 200ppm). The maximum number of pods per plant was recorded in the treatment T3 (ASA @ 200ppm) Maximum pod weight of ten fruits was recorded in the treatment T5 (Ascorbic acid @ 200ppm). The maximum fruit length was recorded in the treatment T5 (Ascorbic acid @ 200ppm). Highest Pod yield per plant was recorded in the treatment T5 (Ascorbic acid @ 200ppm) also. Maximum value of protein content was observed for treatment T3 (ASA @ 200ppm). These results prove that foliar applications of Ascorbic Acid at concentrations of 200 ppm (T5) were beneficial for the growth and development of French bean. Maximum yield per plant was recorded with the treatment application of Ascorbic acid at concentrations of 200 ppm (T5) and was found to be superior over Acetyl Salicylic Acid concentrations. Maximum protein content was recorded with the treatment application of Acetyl Salicylic Acid at concentrations 200 ppm (T3) and was found to be superior over Ascorbic Acid concentrations.

Assessment of Climate Change Impact on Crop yield and Evaluation of Coping Strategy using Crop Growth Simulation Model

Any change in climate will have implications for climate-sensitive systems such as agriculture, forestry and some other natural resources. Changes in solar radiation, temperature and precipitation will produce changes in crop yields and hence economics of agriculture. It is possible to understand the phenomenon of climate change on crop production and to develop adaptation strategies for sustainability in food production, using a suitable crop simulation model. CERES-Maize model of DSSAT v4.0 was used to simulate the maize yield of the region under climate change scenarios using the historical weather data at Kharagpur (1977-2007), Damdam (1974-2003) and Purulia (1986-2000), West Bengal, India. The model was calibrated using the crop experimental data, climate data and soil data for two years (1996-1997) and was validated by using the data of the year 1998 at Kharagpur. The change in values of weather parameters due to climate change and its effects on the maize crop growth and yield was studied. It was observed that increase in mean temperature and leaf area index have negative impacts on maize yield. When the maximum leaf area index increased, the grain yield was found to be decreased. Increase in CO2 concentration with each degree incremental temperature decreased the grain yield but increase in CO2 concentration with fixed temperature increased the maize yield. Adjustments were made in the date of sowing to investigate suitable option for adaptation under the future climate change scenarios. Highest yield was obtained when the sowing date was advanced by a week at Kharagpur and Damdam whereas for Purulia, the experimental date of sowing was found to be beneficial.