Second Year Of Experiment Research Articles

Evaluation of nano urea for the production, economics and greenhouse gases emission reduction in wheat crop

Urea is important source of nitrogen (N) in wheat which is now facing issues of decreasing use efficiency, higher energy inputs and green house gases (GHG) emissions. Nano urea (NU) is recommended at a lower dose for similar yields. In view of this, an experiment was conducted to evaluate the NU and 5% urea (5 U) spray with different levels of recommended dose of nitrogen (RDN). In 2021–22, all the treatments recorded statistically equivalent values for effective tillers; however, different levels of RDN with NU recorded significantly higher values in 2022–23. The grain yield was significantly higher for 75% RDN + NU, at par with 50% RDN + NU during 2021–22, whereas, it was highest with latter during 2022–23. Gross and net returns followed the similar trend during both years. B: C ratio recorded highest values with NU supplementing 25% and 50% of RDN during 2021–22 and 2022–23, respectively. Highest values for output and net output energy were recorded with 75% RDN + NU and 75% RDN + 5 U during first and second year of experimentation, respectively. Supplementing 25–50% RDN with two sprays of NU recorded equivalent reduction in GHG emission. Lodging was recorded only in second year of experimentation, and its score was highest with RDN (19.0), whereas, it was lowest with 50% RDN + NU (2.0). Thus, replacing 50% of conventional urea with two sprays of NU can be a promising strategy for improving wheat productivity, simultaneously reducing the energy inputs and greenhouse gases emission.

Evaluation of seedling cultivation and irrigation regimes on yield and yield components in rice plant.

A split-plot experiment was conducted in a randomized complete block design with three replications in two cropping years at Mazandaran Rice Research Institute to study cultivation and irrigation regimes. The main factor is three-level irrigation regimes, permanent irrigation throughout the day (T1), irrigation two days after water disappears from the soil (T2) and permanent soil saturation (T3) the second factor is three-level cultivation methods., Plowless cultivation (W1), stack 60 cm (W2), and stack 80 cm (W3). Based on the results obtained from the combined analysis, the effect of the year was significant in terms of rainfall, productivity 2, number of tillers, number of empty grains, 1000-grain weight, percentage of the crushed grain, and white rice yield. The effect of the main factor was significant for all traits except productivity 1 and plant height. Based on the results of comparing the mean effect of year × treatment, four treatments, without plowing with permanent irrigation throughout the day in the first and second year of the experiment, cultivation without plowing with irrigation two days after water disappears from the soil in the second year of experiment and cultivation without Plowing with permanent saturated irrigation in the first and second years of the experiment was identified in terms of grain yield as suitable planting methods with appropriate irrigation regimes. Based on the results obtained from the polygon view in different years of the experiment, T3W1, T3W2, and T1W1 treatments can be suggested as desirable treatments in terms of irrigation regimes and cultivation methods in this rice cultivar. According to the ranking diagram of treatments based on traits in the years of experimentation, T1W1, T2W2 and T1W3 were introduced as the most desirable treatments for cultivating this rice cultivar.

Effect of biostimulant raw materials on soybean (Glycine max) crop, when applied alone or in combination with herbicides

IntroductionBiostimulants exert positive functions in plants, improving yield and quality, and alleviating the negative effects of abiotic stresses. Among them, the application of herbicides may cause damage to nontarget plants. At present, limited information is available regarding the interaction between biostimulants and herbicides.MethodsThe purpose of the present study was to assess the effect of an herbicide’s mixture (Harmony® 50 SX® + Tuareg® + Zetrola®), used in combination with several biostimulant raw materials (BRM), on the agronomic and physiologic characteristics of soybean. The experiments were conducted in two seasons, 2020 and 2021, applying the herbicides mixture alone or associated with 10 BRM.ResultsDifferences emerged between the two years, considering nitrate, total sugars concentration, flavonol, and chlorophyll a fluorescence-related parameters. Chlorophyll content significantly declined (−45% in 2020) in plants treated with the herbicides mixture alone but, in combination with potassium silicate, the chlorophyll values were restored to control levels. The same positive effect observed in response to the combination of potassium silicate and the herbicide mixture has been confirmed in the second year of experiment. At the same time, chlorophyll content and Nitrogen Index were positively increased (up to 8% and 30%, respectively) depending on the application of some BRM and the year. A significant effect of biostimulants on yield was confirmed by the application of Ascophyllum nodosum (+16%) and humic acids (+7%), in 2020. However, the combined use with the herbicides nullifies the increase. DiscussionThe results obtained from these experiments support the use of biostimulants in improving specific quality traits (chlorophyll content, leaves nitrogen status, and secondary metabolites accumulation). At the same time, the potential use of biostimulants in combination with herbicides needs to be further explored since of external factors (environment, year…) still have a strong effect on their efficacy.

Nitrogen Application Can Be Reduced without Affecting Carotenoid Content, Maturation, Shelf Life and Yield of Greenhouse Tomatoes

Tomatoes (Solanum lycopersicum L.) of the variety Elpida were grown under standard Mediterranean greenhouse conditions during the spring season at three different nitrogen levels (low 6.4, standard 12.8, high 25.9 mM/plant), which were replicated during two consecutive years. Application of high nitrogen significantly increased the colour index a* (p < 0.001) but did not significantly affect yield or quality. The variety exhibited prolonged postharvest storage at room temperature (median survival time of 93 days). The maturation process was delayed by harvest at the breaker stage (2.5 days, p ≤ 0.001) or by super-optimal temperatures in the second year of experimentation (10 days, p ≤ 0.001). The colour indices L* and a* and the hue angle (a/b*) were positively correlated with the sum of total carotenoids, while differences in b* depended on the year of cultivation. The sustainability of this type of tomato production can be improved by reducing the nitrogen supply to less than the current standard practice, with minimal risk or negative effects on yield and quality of tomatoes.

Spore Abundance and Morphology of Arbuscular Mycorrhizal Fungal under Conservation Agriculture

Soil is full of microbial diversity and microbes present in soil interact diversely with other living form present in soil e.g., soil microbes and plants. These interactions range from symbiosis to parasitic. Among these, the most predominating mutualistic symbiotic relation is mycorrhiza (associated with ∼80% of terrestrial plant species), formed between arbuscular mycorrhizal (AM) fungi and vascular plants. An experiment was conducted under three cropping system rice-maize-cowpea (RMCp), rice-wheat-green gram (RWGg) and rice-cauliflower-bororice cropping (RCfBr) to study influence of three different tillage intensities i.e., CT (conventional tillage), RT (reduced tillage), and ZT (zero tillage) with five different levels of fertilizer and residue application, R1 (0%Residue &amp; 100%RDF), R2(100%Residue &amp; 50%RDF), R3 (100%Residue &amp; 75%RDF), R4 (50%Residue &amp; 100%RDF), R5 (50%Residue &amp; 75%RDF), on AMF spore load and diversity.The experimental design followed was split plot with tillage was main plot treatment and residue as sub plot treatment. Result showed that AMF spores and diversity are significantly influenced of degree of soil disturbance under different tillage practices and cropping system in practice, however residue application imparted non-significant influence on AMF spore load and diversity. A significant lower spore count was observed under CT as degree of soil disturbance is excessive high under CT compared to RT and ZT. With respect to spore diversity, round (shape), brown (color) and free spores were predominating spore type. In reference to spore shape abundance sequence was round&gt;spherical&gt; oval while for spore color it was brown&gt;yellow&gt;hyaline and &gt;90 % spore was free while attached spores were &lt;5%. In case of AMF spore count influence of cropping system was more prominent compared to other factors (i.e., tillage and residue). In RMCp and RWGg, significant increase inspore count was observed compared to RCfBr cropping system. On second year of experimentation, in RCfBr cropping system a significant decline in spore number was detected due to inclusion of cauliflower which act as non-host of AMF. Hence to attain benefits associated with AMF to arable crop we must reduce level of soil disturbance and avoid crucifer crops in cropping system.

Impact of Different Tillage Practices and Pre-mix Herbicides on Growth Indices of Wheat Crop

Growth indices changes from sowing till harvesting of the crop were monitored under the influence of four tillage options (zero tillage no-residue, zero tillage with residue, conventional tillage no-residue and conventional tillage with residue) and four weed management practices (sulfosulfuron + metsulfuron @ (30+2) 32g a.i. ha-1, clodinafop propargyl + metsulfuron methyl @ (60+4) 64 g a.i. ha-1, weed free (30 and60 DAS) and weed check) during rabi season of 2019-20 and 2020-21. Analysis of the two years average data indicated that conventional tillage with residuealong with application of clodinafop propargyl + metsulfuron methyl @ (60+4) 64 g a.i. ha-1resulted in the highest significant values of crop growth rate (CGR)and leaf area duration (LAD) up to 90 DAS after which it declineswhereasrelativegrowth rate (AGR) shows a declining trend from sowing till harvesting.Net assimilation rate (NAR) was found to be unaffected by the treatment during first year of experimentation.However, it was significantly affected during second year of experimentation which declines from sowing to harvesting. No interaction effect was found among different treatments. The overall findings concluded that conventional tillage with residue along with application of clodinafop propargyl + metsulfuron methyl @ (60+4) 64 g a.i. ha-1could be more beneficial in the study area.

Effects of zeolite and biofertilizers on yield components, yield and nutrients uptake in grains of two corn cultivars (cv. 6010 and ns71)

In order to study the effects of zeolite and biofertilizers on yield components, yield and nutrients uptake in grains of two corn cultivars (cv. 6010 and ns71), a field experiment was conducted as split plot in a randomized complete block design with three replications at Neka, Mazandaran province, Iran in 2017 and 2018. The corn cultivars cv. 6010 and ns71 were the main plots and applications of zeolite and biofertilizers in 6 combinations including the zeolite application, Bacillus sp., arbuscular mycorrhizal fungi (AMF), applications of zeolite + Bacillus sp., applications of zeolite + AMF and applications of zeolite + Bacillus sp. + AMF were considered as sub-plots. The results showed that by applications of zeolite + Bacillus sp. + AMF, increased the yield components and seed yield of corn. The maximum seed yield (4.48 t ha−1) was obtained with simultaneous application of zeolite and biofertilizers, and the yield decreased with separate application of zeolite by 31.2%. Among two cultivars used in the experiment, the ns71 cultivar was superior to 6010 cultivar in terms of seed yield. The seed nitrogen content was significantly increased in both cultivars during the two cropping seasons by AMF application. The combined application of zeolite + Bacillus sp. + AMF resulted in the highest amount of seed phosphorus (0.3910 ppm) in the ns71 cultivar in the second year of experiment. Therefore, the combined application of zeolite and biofertilizers is recommended to increase the quantitative and qualitative yield of corn.

THE INFLUENCE OF BACTERIAL INOCULATS ON PATHOGENS, YIELD AND QUALITY IN SOYBEAN CROP

The paper aimed to present the influence of bacterial inoculation,applied to seeds, on the attack of pathogens, on yield, yield elements and quality in soybean crop.A two-year experiment was carried out at Research and Development Station for Agriculture Turda (RDSA Turda), in 2019-2020. Teo TD, an early soybean variety was used in the experiment. Seed stimulation was conducted with two nitrogen-fixing bacteria: Bradyrhizobium sp. JHI and Paenibacillus graminis FL400. The application of bacterial inoculants leads, in the second year of experiment, to an increase in soybean yield with 903 kg/ha, 39.8% higher compared to the control, when Bradyrhizobium + Paenibacillus was applied. Biostimulation also help the plant fight against pathogens with a positive impact on number of nodules, yield elements and quality parameters.

Diversification of Rice–wheat Cropping System Improves Growth, Productivity and Energetics of Rice in the Indo-Gangetic Plains of India

Rice–wheat cropping system plays a vital role in ensuring food security of India. However, the long-term sustainability of the system is often questioned due to several problems associated with it. Diversification of the rice–wheat cropping system with suitable crops could be a possible solution. Thus, a field experiment consisting of ten rice-based cropping sequences was conducted in a randomized block design with three replications at Banaras Hindu University, Varanasi, India, for two consecutive years to study the effects of crop diversification on rice performance. The effect of crop diversification on rice was found to be significant only during the second year of experimentation. Results showed that rice–berseem–cowpea fodder followed by rice–potato–green gram sequence recorded highest growth, yield, nutrients uptake, protein yield, carbohydrates yield, economics and energetics of rice. Rice–berseem–cowpea fodder sequence recorded significantly higher number of panicle m−2 (16%), grain yield (13.9%), straw yield (13.6%), total N, P, K uptake (17.2, 21.7, 17%, respectively), protein yield (14.6%) and carbohydrate equivalent yield (13.9%) over rice–wheat cropping sequence. In addition to above, rice–berseem–cowpea fodder sequence also proved significantly superior to rice–wheat cropping sequence and recorded higher gross returns (13.9%), net returns (46.6%), net energy (15.9%), energy productivity (13.8%) and energy intensity (13.9%). Rice–berseem–cowpea fodder and rice–potato–green gram were found the most suitable cropping sequence to diversify rice–wheat cropping system in the Indo-Gangetic plain for better performance of rice.

Amino acid composition and protein quality of Tepary bean grains (&lt;em&gt;Phaseolus acutifolius &lt;/em&gt;L.) as affected by sowing date and planting pattern under semi-arid condition

Planting pattern and sowing date are the eminent factors affecting plant growth and development. The two-year experiment under field conditions was conducted as split plot design in three replications during 2017 and 2018. The main plot was planting pattern in two levels (PP1: one-row, and PP2: two-row plantation pattern) and subplot was sowing date in three levels (SD1: June 15, SD2: June 30 and SD3: July 15). The results revealed that the biological yield in SD2 had significant increase by 14% and 6% in comparison to SD1 and SD3 under two-row plantation pattern in the first year respectively. In PP2, the seed yield was improved by 19% and 15% compared to SD1 and SD3 at SD2 in 2017. Carbohydrate content varied in the two years. In mono row plantation method, the grain carbohydrate content was higher in SD1 significantly. In bean plants under PP2, protein content on SD2 increased by 13% compared to SD3 in the second year of experiments. The greatest amount of essential amino acids was found in leucine followed by lysine, arginine, phenylalanine, valine, isoleucine, histidine, and threonine. We found that the concentration of essential amino acid in tepary bean grains was significantly changed by sowing date. We suggest that in tepary bean cultivation the use of plantation pattern is very effectiveness and two-row plantation pattern was the most important when the sown date delayed by late of June under same experimental environment.

Influence of kaolin application on most important fruit and leaf characteristics of two apple cultivars under sustained deficit irrigation

BackgroundApple is one of the oldest and most valuable fruits. Water restriction is one of the major problems in the production of this fruit in some planting areas.MethodsEffects of kaolin spray treatments were studied on two early apple cultivars of Golab and Shafi-Abadi under sustained deficit irrigation (SDI) in Alborz province, Iran during 2017 and 2018. Irrigation treatments were 100%, 85%, and 70% ETc and kaolin application were concentrations of 0, 3 and 6% in 2017 and 0, 1.5 and 3% in 2018.ResultsResults showed that 85% ETc treatment compared to other irrigation treatments improved apple tree crown volume in 2017. Deficit irrigation treatments significantly reduced fruit weight in both years. Application with 6% kaolin resulted in 33.3% increase in apple fruit weight compared to non-kaolin treatment at 100% ETc irrigation in the first year. Severe deficit irrigation (70% ETc) significantly reduced apple fruit length in both years, but 6% kaolin increased fruit length in both apple cultivars in 2017. Severe deficit irrigation treatment increased the firmness of apple fruit compared to control and mild deficit irrigation (85% ETc) in the first year of experiment. There was no significant difference between irrigation treatments for apple fruit firmness in the second year of experiment. Kaolin treatments of 1.5% and 3% at full irrigation increased the soluble solids content of apple fruit by 36.6% and 44.1% in 2018, respectively. Deficit irrigation treatments significantly increased leaf proline content compared to control in both years. In the first year, kaolin treatments increased leaf proline but in the second year, leaf proline was not significant. Deficit irrigation treatment of 70% ETc and 6% kaolin had the highest amount of glycine betaine content, malondialdehyde and hydrogen peroxide in apple leaf in the first year of experiment.ConclusionsSevere deficit irrigation stress (70% ETc) increased the activity of nonenzymatic defense systems of apple trees. Kaolin as a drought stress reducing agent can be recommended in apple orchards of Golab and Shafi-Abadi cultivars as an effective and inexpensive method to improve tolerance to drought stress conditions.

Effect of different level of sulphur on growth and yield of lentil crop: A review

Efficient use of sulphur doses, the biological, grain and straw yield of lentil crop are significantly higher as compared with control control during first and second year of experimentation. On the basis of economics, application of sulphur/ha is significantly best for achieving higher gross income and benefit cost ratio of lentil as well as economically more net return. This study aims at reviewing the effect of different level of sulphur on growth and yield of sulphur. Sulphur showed a synergetistic effect on yields of lentil. Protein content increases significantly with increase of sulphur. Imformation gained from from this study can be utilized to develop more efficient sulphur fertilization levels in winter lentil.

Delayed irrigation: An approach to enhance crop water productivity and to investigate its effects on potato yield and growth parameters

Highly efficient irrigation and conservative sowing practices are required at the farm level for sustainable crop production. For the purpose, a field experiment on autumn potato crop was conducted during the years 2014–15 and 2015–16 to maximize crop water productivity. Five treatments with two sowing configurations were designed i.e. ridge sowing under furrow irrigation (RF), bed sowing under furrow irrigation (BF), and three drip irrigation treatments for different Management Allowed Depletion (MAD) levels under bed sowing i.e. irrigation when 20% (DIR1), 35% (DIR2), and 50% (DIR3) of the available plant water depleted from the soil. Results revealed that drip irrigation treatments influenced potato yield (P ≤ 0.05), the highest yield during both the years were recorded in the control treatment (RF) measured as 49.65 and 42.55 tons ha−1 respectively. The maximum number of total potato tubers m−2 were found in treatment DIR2 while control treatment (RF) was at par of others in terms of marketable tubers. The maximum percentage of green (3.81, 3.75), rotten (2.95, 2.20), damaged (2.10, 2.87), and cracked (2.33, 1.79) tubers were observed in ridge sowing under furrow irrigation (RF) during both years of experiment. The maximum water saving was achieved by 50.33% and 42.66% in DIR3 as compared to control one (RF) whereas maximum crop water productivity in kg m−3 was achieved in DIR2 (i.e. 13.01, 13.60) during the first and second year of experiment respectively. In conclusion, bed planting under furrow and drip irrigation treatments proved superior to control practice (RF) in terms of water saving, water productivity, total number of tubers, and different other plant growth parameters. However, further studies on nutrient management are recommended for the bulking of non-marketable tubers in bed planting method which ultimately enhances yield and net return to the farmers.

Boron content in soils under increasing magnesium and sulphur doses in a field experiment

The three-year field experiment (2015–2017) with graded doses of magnesium (Mg) and sulphur (S) was carried out at the Humpolec experimental station (49.5546239N, 15.3485489E; Czech Republic). The interactions between boron (B), Mg and S in the soil were studied. No boron was applied into soils. Contents of B, S and Mg in the soil were determined by the Mehlich 3 and NH&lt;sub&gt;4&lt;/sub&gt; acetate methods. The crop rotation was: spring barley-oilseed rape-winter wheat. Three Kieserite doses (S and Mg fertiliser) were applied. Sulphur treatments were 10-20-40 kg S/ha to cereals and 20-40-80 kg S/ha to oilseed rape. The doses of Mg were: 13-26-52 kg Mg/ha to cereals and 26-52-104 kg Mg/ha to oilseed rape. A significant gradual decrease of B-Mehlich 3 was observed under Kieserite treatments during the experiment (from 1.24 mg B/kg in control in the 1&lt;sup&gt;st&lt;/sup&gt; year to 0.92 mg B/kg in the 3&lt;sup&gt;rd&lt;/sup&gt; year). On the contrary, B-NH&lt;sub&gt;4&lt;/sub&gt; acetate contents in soils remained similar during 2015–2017 in control soils (0.33–0.39 mg B/kg) and significantly decreased under Kieserite treatments, namely by 55–57% in 2016 and by 43–48% in 2017. A significant decrease of B content in soils was noted since the second year of experiment after oilseed rape. The boron contents in soils were affected in several ways – by adsorption of B on magnesium oxides and other substances, exchange with SO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;2–&lt;/sup&gt; anions and possible leaching, and also by the uptake by grown crops, mainly oilseed rape.

Tomato yield as a function of water depths and irrigation suspension periods

ABSTRACT Irrigation management is essential for tomato fruits yield and quality. Therefore, the aim of this study was to evaluate the yield of tomatoes for industrial processing, ‘BRS Sena’ hybrid, subjected to water depths and irrigation suspension periods before harvest, irrigated by subsurface drip irrigation, in Goiás, Brazil (17º 49’ 19.5” S and 49º 12’ 11.3” W), in 2015 and 2016. The experiments were conducted under a randomized complete block design, with four replications, in split plots. Five irrigation levels (50, 75, 100, 125 and 150% of crop evapotranspiration) were evaluated in the plots and five irrigation suspension periods (0, 7, 14, 21 and 28 days before harvest) were evaluated in the subplots. At 125 days after transplanting the seedlings, the yields of green, mature, rotten fruits and total yield, water productivity and percentages of green, mature and rotten fruits were evaluated. The highest total fruit yields (105.86 and 58.60 t ha-1) were obtained with water replacements ranging from 125.47 (615.09 mm) to 132.11 (564.00 mm) of crop evapotranspiration, in the first and second year of experiment, respectively. Growing plants under water deficit and excess increased the incidence of rotten fruits and decreased that of mature fruits. Pre-harvest irrigation suspension reduced crop yield and incidence of green fruits and increased the incidence of rotten fruits. The highest water productivity by the crop occurred under water deficit, management that may be interesting for regions with water restrictions.

Nitrogen fertigation schedule and irrigation effects on productivity and economics of spring sugarcane

The field experiment was conducted to find the appropriate irrigation method, fertilization schedule and its influence on growth, yield and quality of sugarcane. The soil of the experimental site was sandy clay loam, neutral in reaction (pH 7.7), low in organic carbon (0.41%) and available nitrogen (167.0 kg ha-1), medium in available phosphorus (19.1 kg ha-1) and potassium (208.0 kg ha-1). Experiment was laid out in split plot design with four replications. The treatments consisted of three irrigation methods in main plot viz., flood, furrow and drip; five nitrogen scheduling in sub plot viz., farmers practice, 4 splits, 6 splits, 8 splits and 10 splits. In flood method of irrigation all growth and quality parameter were recorded lowest. Thus, it may be concluded that to achieve highest millable cane and quality parameters, drip irrigation is a better option. The number of tillers (177.2 thousand ha-1), number of millable canes (123.3 thousand ha-1), cane length (367.98 cm), cane yield (168.51 t ha-1), commercial cane (CCS) yield (25.05 t ha-1) and economic return were found significantly higher under drip irrigation during first year. Similar trends were recorded during second year of experimentation. The highest dry matter accumulation and crop growth rate were also recorded under drip irrigation during both the years. Similarly, water use efficiency and water productivity were found maximum under treatment of drip irrigation. Significantly highest number of tillers (165.6 thousand ha-1), millable canes (116.3 thousand ha-1), cane yield (154.72 t ha-1), dry matter accumulation, crop growth rate, CCS yield (23.39 t ha-1) and economic return were recorded with 6 splits of nitrogen application. The overall effect of nitrogen scheduling was in the order of 6 splits &gt; 8 splits &gt; 10 splits &gt; 4 splits &gt; farmer’s practice.

Application of phosphine fumigant for controlling rice storage insect pests in foundation seeds: Poster

The development of phosphine resistance in storage insect pests is now problematic, so the increase of rate and frequency of phosphine fumigation in a storage room is needed. However, an adverse effect on seed germination, and human hazard needs to be tested. This experiment was aimed to find the most suitable methods used in combination with phosphine fumigation to reduce the risk of phosphine exposure. The treatments were (1) phosphine fumigation for 7 days and then open a plastic cloth (2) phosphine fumigation for 7 days and continue to cover a plastic cloth (3) phosphine fumigation for 7 days and spray pirimiphos methyl on sack (4) phosphine fumigation for 7 days and use a light trap (5) treat seeds with sweet flag powder before phosphine fumigation for 7 days (6) no phosphine fumigation with plastic cloth opening and (7) no phosphine fumigation with plastic cloth covering. In each treatment, seeds were sampled every month for 12 months to determine seed quality and insect populations. The results showed that seeds treated with sweet flag powder and fumed with phosphine for 7 days can significantly control storage rice insect pests in the first and the second year of experiments. The seed moisture content in each treatment changed in a similar pattern throughout 12 months storage in both years (13.4 – 13.7%). The seed germination showed similar results (more than 80% after 6 months storage), except the treatment of 7 days phosphine fumigation with plastic cloth covering which resulted in a slowly decline in germination. Seed weight losses and numbers of insect pests in the treatment with sweet flag powder were significantly less than the others.

The importance of adaptive expertise in CAD learning: maintaining design intent

ABSTRACTIn CAD modelling, there is no one general standardised teaching-learning methodology. We use the strategic-learning methodology, maintaining design intent, fully aware that it is necessary to modify CAD models for their reuse. Questions concerning the thought processes of students when modelling with CAD and the strategies that they choose that best maintain design intent arise in the course of using the 3D modelling programmes. Our aim here is to determine the importance of adaptive expertise in the results of CAD models and, particularly, in one of its constructs: design intent. To do so, CAD-based experimentation took place over two years with 78 third-year students in the first year and with 53 third-year students in the second year from the subject module of Graphic Engineering, on the Degree in Mechanical Engineering of the University of Burgos (Spain). At the start of the year, the students conducted a survey to measure adaptive expertise. Subsequently, in the first year of experimentation, the students prepared various CAD models and the design intent was evaluated in one of them (a connecting rod or conrod), broken down into the skeleton, the structure, the modifications and the constraints. In the conrod exercise, the students also completed a questionnaire both before and after designing their models, which were analysed to detect the thought processes and the strategies that they had applied. In the second year of experimentation, design intent was incorporated in various exercises at the beginning of the year, in addition to the conrod. The main conclusion is that the correct division of the part into its pieces and adaptive expertise improved the results in relation to design intent in the CAD.

Effect of prohexadione-Ca on leaf chlorophyll content, gas exchange, berry size and composition, wine quality and disease susceptibility in Vitis vinifera L. cv Xinomavro

Abstract In this study, prohexadione-Ca was applied at bloom and postbloom stages to field-grown cultivar Xinomavro to evaluate the effects on leaf chlorophyll content, water potential, photosynthesis, grape, berry size and composition and wine quality. The results showed that prohexadione-Ca increased the chlorophyll contents and net photosynthesis in early growth stages (berry set, veraison). Its effect was gradually reduced in later growth of stages. In addition, prohexadione-Ca affected the stomatal conductance mainly at later stage. In contrast, it did not show any effect on the water potential. It was also shown that the prohexadion - Ca reduced the berry size and increased skin anthocyanin and phenolic compounds. Wines provided from treated vines had improved colour and sensory attributes. Applications with prohexadione-Ca improved the resistance of grapes to Botrytis bunch rot in the first year of experiments. In contrast, no significant difference on susceptibility of grapes to Botrytis bunch rot was found in the second year of experiments. No effect of prohexadione-Ca on the susceptibility of vines to downy mildew and powdery mildew was found.

Unpuddled transplanting: A productive, profitable and energy efficient establishment technique in rice under Eastern sub-Himalayan plains

The study was undertaken in sandy loam soils of Eastern sub-Himalayan plains with the objectives to arrive at optimal tillage requirement in rice to economise on fuel, labour, time and energy and also to judge the performances of different promising varieties of this zone under those alternative crop establishment techniques for getting higher profitability. The experiment was laid out in a split-plot design having 20 treatment combinations in 3 replicates. Four different crop establishment methods viz., direct seeding through zero till drill (DSR), bed planting (BP), unpuddled transplanting (UPTR) and puddled transplanting(PTR) in main plot and five different varieties viz., Swarna sub 1, Pratiksha, IET 5656, Naveen and MTU 7029 in sub plots were allocated randomly. It was revealed that PTR recorded significantly higher grain yield (4502 kg ha −1) in the first year, while UPTR recorded maximum grain yield (4616 kg ha −1) during second year of experimentation, being at par with PTR (4606 kg ha−1). Grain yield varied significantly among the varieties in both the years of experimentation. Swarna Sub 1 (3779 kg ha−1) in first year and Pratiksha (4215 kg ha−1) in second year recorded maximum grain yield. Use of machineries under alternate cop establishment techniques reduced the fuel, labour and time requirement under those alternate crop establishment techniques. The total energy input in rice were reduced to 9269.95, 7865.00 and 7589.30 MJ ha −1 under UPTR, BP and DSR, respectively, due to less fuel and labour requirement as compared to PTR(10862.30 MJ ha −1). It was interesting to note that despite higher output energy and net energy gain under PTR, energy efficiency was recorded maximum under UPTR (15.88) reflecting its higher efficiency over other crop establishment techniques. Despite higher gross returns under PTR, UPTR reflected a higher net return in both the years of experimentation. As the yields were similar in PTR and UPTR, reduced cost of cultivation under UPTR resulted in much higher net returns for all the varieties. It can be concluded that unpuddled transplanting in rice would be the most viable option in rice-wheat cropping system in Eastern sub-Himalayan plains in terms of productivity, energy-efficiency as well as profitability.