International Journal of Plant Production
Volume:11 Issue: 1, Jan 2017

Development of drought-tolerant cultivars is hampered by a lack of effective selection criteria. In this research, response of 36 genotypes of rapeseed from seven species of Brassica including B. napus, B. rapa, B. juncea, B. carinata, B. oleracea, B. nigra and B. fruticulosa was assessed under three moisture levels (no stress, mild stress and intense stress) in the field during 2011-2012. Five drought-tolerance indices were calculated: stress tolerance (TOL), stress susceptibility index (SSI), mean productivity (MP), geometric mean productivity (GMP) and stress tolerance index (STI). Increasing water stress levels caused significantly more reductions in the seed yield of all species. Species B. napus had the highest yields in normal and intense stress conditions while B. carinata showed better performance in mild stress condition. Correlation coefficients revealed that among drought tolerance indices, GMP, STI and MP are superior criteria for selecting high-yield genotypes under stress and non-stress conditions. B. napus and B. carinata were the most drought tolerant while B. rapa and B. oleracea were the most susceptible species of Brassica based on yield potential. Application of principle component analysis (PCA) for distinguishing drought and susceptible species are discussed.

A research was conducted in Southern Italy to study the changes in seed yield, oil content and fatty acids composition, in response to irrigation at different stages of growing season (at sowing, Dry; from sowing to beginning of flowering, S-BF; from visible bud to 75% flowering, VB FF; from beginning of flowering to seed ripening, BF-M; from sowing to seed ripening, Full), in a standard sunflower hybrid sown at normal (April) and late (June) time. High seed yield and oil content combination resulted in the significantly greatest oil yield in ‘Full’ water regime. MUFAs (mostly oleic acid) were higher in late sowing and they benefit from good soil water availability of ‘Full’ regime. Contrastingly, PUFAs (i.e. linoleic acid content), higher in late season, was depressed by good soil availability during the early growing season (S-BF and S-M regimes). Irrigation at critical stages (i.e. flowering) may alleviate the negative impact of water stress upon crop productivity and oil fatty acids composition, resulting in yield and oil quality benefits besides a water saving. Late sowings allow cultivating sunflower as a catch crop, with an increased economic and environmental sustainability of Mediterranean farming systems.

The aim of this experiment was to determine the response of dill (Anethum graveolens L.) to water deficiency and salinity. In spring, dill biomass decreased with increasing water deficiency due to a reduction in the number and mean weight of leaves per plant. The concentrations of chlorophyll, carotenoids, vitamin C and total phenolics within the leaves were unaffected by water stress, but the Cl, Na and K content decreased. Salinity had no effect on plant growth in the spring, except at the highest level (8 dS/m-1), where a decrease in biomass occurred. The chlorophyll and total phenolics content of leaves rose in the autumn with increasing salinity, whereas vitamin C and carotenoids were unaffected. In spring, increasing salinity caused fluctuations in the chlorophyll and vitamin C content of the leaves and a decrease in total phenolics. The concentrations of chlorophyll and antioxidants were higher in spring than in autumn at all levels of salinity. The essential oil content was also higher in the spring than in the autumn, irrespective of salinity. A relative decrease in dill ether within the herb oil under increasing salinity was compensated for by an increase in α-phellandrene. In the flower oil, increasing salinity caused a decrease in the relative concentrations of both α-phellandrene and dill ether, which was compensated for by an increase in carvone. Overall, dill appears more resistant to salinity than to water stress, but the season of cultivation has the most important effect on both yield and quality.

Maize is one of the major crops in China and its yield potential has been changed significantly by climate change induction during last five decades. The national policy of maize production sufficiency emphasizes the necessity for a more accurate estimation of yield potential of maize at a national level. In this paper yield potential of maize was calculated using the Global Agro-Ecological Zones (GAEZ) model and key meteorological factors impact on yield potential across China was also analyzed. The results shows that, total yield potential of maize increased by 0.15 million tons/year during the past five decades due to an increase in cultivated area as a result of climate change impact. The partial correlation analysis between main meteorological factors and yield potential of maize at a county level showed that 47% of the counties of China were predominately influenced by changes in solar radiation while 16% of counties were predominately affected by temperature changes. In addition, each agricultural zone showed clear spatial difference in the distribution of key impact factors. These research findings will not only provide scientific basis for making good use of meteorological resources under climate change, but also play a vital role for the management of national maize production for food security.

The reconciliation of economy and environment is a key factor in achieving sustainability. The European Union wishes to achieve the sustainability of its agriculture in order to produce high quality food materials and to manage energy crisis and the risks related to climate and market fluctuations. These risks can be mitigated by reducing negative impacts of agricultural activities on the environment. Therefore, this study was designed to derive and promote the potential tools to increase the land area under grain legumes in Midi-Pyrenees region (France) where it currently stands at only 1 to 3%. For this purpose modeling chain APES FSSIMIndicator was used to assess different alternative scenarios of proposition of new grain legumesbased cereals rotations, provision of higher premium on grain legumes, increase in sale price and yield of grain legumes, reduction in price and yield variability of grain legumes and combination of all these scenarios. Results showed that alternative scenario of provision of more premiums on grain legumes was more efficient in increasing the grain legume area than other alternative scenarios, but this would require a level of subsidies much higher than the current crop-specific subsidies in EU. However, in case of combination of all these scenarios, theincrease in grain legumes area was maximum for all three selected farms from the study area. In addition farm income was increased by 11 to 26% and energy consumption was decreased by 4 to 9% for the selected farms. It is concluded that grain legumes area in Midi-Pyrenees farming systems can be increased by following the above mentioned alternative strategies .

Optimized nitrogen (N) management reduces total N application without sacrificing crop yield. However, the underlining mechanisms have not been well investigated, especially lacking the evidence from roots. Here we performed a two-year field experiment with maize grown under zero-N, conventional N and optimized N applications and examined grain yield, N, phosphorous (P) and potassium (K) uptake and root length in diverse diameter classes. Results showed that both conventional N and optimized N managements significantly increased plant nutrient contents and grain yield compared with zero-N treatment, but no obvious difference was observed between the two N-fertilized treatments. Notably, the response of different nutrients to N application was not synchronous temporally over the growth period, following the order of N first, P second and K last. Though N application generally had minor impact on total root length and root biomass, optimized N regime significantly increased fine root (diameter ≤ 0.2 mm) length compared with conventional N at the eighth leaf emerged stage. The stimulated fine root growth under optimized N management is beneficial for adequate N uptake during the key growth stage, which determines subsequent PK acquisition and final crop yield. Our findings highlight the importance of fine roots in maize NPK uptake and a better understanding of the response of fine roots to changes in N availability may therefore be critical for optimizing N input in maize farming system.

Selecting and cultivating the crops/varieties that can tolerate water salinity is potentially an important strategy to save fresh water resources and maximize the crop yield in salt affected areas. To evaluate the responses of 36 sorghum lines and cultivars to salinity stress, two field experiments were conducted in non-stress (EC=2 dS/m) and salinity stress conditions (EC=12 dS/m) using randomized complete block design with three replications. The field experiments were carried out at research station of Agricultural Research Center and Natural Resources of Yazd, Iran in 2014 and 2015 growing seasons. Under salinity stress conditions, grains/panicle, panicle length, 1000 grain weight, grain yield, biological yield and harvest index were decreased 36%, 15%, 42%, 64%, 40% and 39%, respectively. The highest grain yield under non stress conditions was produced by KDFGS2 (8182.6 kg/ha) while the highest grain yield under salinity stress conditions was achieved by KDFGS6 (3310 kg/ha). Correlation coefficients between grain yield (for both conditions) and tolerance indices showed that geometric mean productivity (GMP), stress tolerance index (STI) and harmonic mean (HAM) indices were appropriate for screening high-yielding genotypes. Principal component analysis validated the results of screening methods and introduced lines number 1, 7 and 9 as superior genotypes under both conditions. Lines number 2, 8, 15, 19, 29 and cultivars Ghalami-Herat, Sepideh and Kimia showed greater sensitivity to salinity stress. Since lines number 4, 6, 10 and 24 had greater yield stability, it appears that they may worth further explorations in future breeding projects.

The paper presents smallholder farmer's perceptions on attributes of bread wheat varieties based on primary data collected from 524 households in four major wheat growing areas of Ethiopia. The results indicated high value of attainment indices for improved varieties compared to landraces, which shows how the demanded attributes are embodied more in improved ones. Grain yield and yellow and stem rust resistance are attributes that are desired mostcompared to others. However, there is high variability in attainment indices among improved varieties for the different attributes, which suggests the need to target varieties for the different environments including disease and drought tolerance. The results also showed inconsistency between the value of attainment indices of varieties and the amount of seed supplied by the formal sector, which resulted in mismatch between demand and supply leading to considerable carryover seed. The formal sector needs to consider diversifying its bread wheat varietal portfolio and increase its capacity for seed supply to respond to emerging challenges and effectively address farmers’ preferences.

A field experiment was conducted to compare the effects of long-term tillage and crop residue management on some physical properties and nitrate leaching of a Typic Haploxerert soil under winter wheat (Triticum vulgare L.)-soybean (Glycine max L.) double-cropping system. The tillage systems consisted of conventional tillage with stubble (CT1), conventional tillage with stubbles burned (CT2), heavy disc harrow reduced tillage (RT1), rototiller reduced tillage (RT2), reduced tillage with heavy tandem disc harrow fallowed by no-tillage (RNT) and no-till (NT). Each tillage method applied at 480 m2 plot and replicated three times in randomly distributed plots. In the experiment, organic matter content (OM), aggregate stability (AS), penetration resistance (PR), porosity, bulk density (BD) in 0-15 cm and 15-30 cm depth and nitrate concentrations at 90 cm depth were determined. Tillage practices significantly affected the measured properties at both soil depths. The BD and PR within the conservational managed plots were higher than under conventional managed plot. Whereas, OM content and AS were significantly greater under conservational managed plots, indicating improved soil quality. Soybean yield was not affected by tillage practices. The concentrations of NO3-N leached had strong variation within sampling dates and significantly different among treatments afterthe first and the third irrigation (P˂0.01). The highest average NO3-N (1440.8b±74.9 mg L 1) in leachate was measured in the CT2 plot while the lowest value (774.8a±56.5 mg L-1) was obtained in the RT1 plot. The results of this study revealed that reduced tillage and no till treatments could significantly improve soil physical quality and reduce NO3-N leaching of Typic Haploxerert soil in the Çukurova Region

China’s sugar production and consumption continues to increase. This process is already ongoing for over 15 years and over 90% of the sugar production comes from sugarcane (Saccharum officinarum). Most of the sugarcane is planted in the south (e.g. the Chinese provinces of Yunnan, Guangxi, Guangdong and Hainan) and it represents there a major economic crop in these landscapes. As found virtually worldwide, climate change is generally expected to influence such suitable planting areas. Here we started a first empirical assessment how climate change would influence the spatial distribution of those current and future suitable planting areas of this strategic crop in China. We employed an ensemble machine learning algorithm (Random Forest; bagging) and increasingly used and robust species distribution models (SDMs). These are based on our compiled and best publicly available crop data sampled from the Chinese sugarcane industry map. They were linked with bioclimate variables from the Worldclim database. This powerful concept allowed us to project sugarcane’s current and future (2070) suitable distributions based on the climate niche. Our results were extrapolated to three Global Circulation Models (GCMs; BCC-CSM1-1, CNRM-CM5 and MIROC-ESM) under three representative concentration pathways (RCPs of 2.6, 4.5 and 8.5). The evaluations of these models indicated that our results had a powerful performance (AUC=0.97, TSS 0.96) for robust inference. Bioclimatic variables related to temperature were the most important predictors for sugarcane planting. All models showed similar increasing spatial trends in suitable distribution area and just a few original suitable areas would be lost. Our finding puts emphasize on new growing areas, their soil and management. It is the first to provide the necessary background in the future to safely cultivate sugarcane in climate-suitable areas and to obtain more sugar production for farmers and the industry; it is of large and strategic importance for food security and national autonomy of this central commodity.

Development and use of crop growth models is an effective tool for agricultural planning and decision making in agricultural industry. Besides, the drought and limited supplies of water in many areas of the world has increased attention to favourable strategies in farm management such as efficient irrigation and planting methods. The objective of this study was to develop a crop model for safflower known as a multi-purpose crop under various irrigation regimes, planting methods and nitrogen fertilization. The experiment was designed as split-split plot that arranged in randomized complete blocks with irrigation strategy as the main plot, planting method as the subplot and nitrogen levels as the sub-subplot in three replications. The irrigation strategies consisted of ordinary furrow irrigation (OFI) and variable alternate furrow irrigation (VAFI) as a partial root drying (PRD) technique. The planting methods were on-ridge planting (P1) and in-furrow planting (P2) methods. The fertilizer levels were 0 (N0), 100 (N1) and 200 (N2) kg ha-1 of urea as 0, 46 and 92 kg N ha-1. Two years of the experiment carried out in a semi-arid area from 2012 to 2014. The field data of the second year of experiment were used to develop the model and it was validated by the data of first year. The results indicated that the proposed safflower model is able to estimate evapotranspiration, soil water content, leaf area index, soil surface evaporation, crop transpiration, biomass, straw and seed yield of safflower in an appropriate manner. The safflower model is useful for having better field management and reducing administrative costs with respect to the model simplicity and its briefness in data input.

A long term study was done to assess the impact of on farm reservoirs (OFR) on oil seed and cereal based cropping systems with vegetables (okra, tomato and carrot) in semi-arid alfisol of southern Telangana region. Two supplemental irrigation (SI) depths (30 and 50 mm) from OFR with raingun system were studied for assessing the water productivity and profitability of the technology in these cropping systems. Cropping system using sole crop of groundnut or maize, later was found to be more profitable (3 times) with 50 mm SI in 2 critical growth stages having annualized net benefit (ANB) of $ 971 - 998 / ha and economic productivity (EP) of 31 Cents / m3 under different capacities of OFR (500-1500 m3). In rainy season with single filling of OFR and deficit irrigation of 30 mm SI, maize뚉骶 was found to be more profitable (ANB: $ 1659 - 2325 / ha and EP: 37 - 5 Cents / m3) as compared to sole crop or with okra. During rainy season and post-rainy season with second filling of OFR at SI depth of 30 mm, maize뚉骶辜檺 was the most profitable option (ANB: $ 2544 - 3012 / ha and EP: 37 - 45 Cents/ m3) as compared to any other combination of the crops. The study revealed that the best economical crop combination under deficit irrigation of 30 mm will make the rainfed agriculture more remunerative with OFR technology with efficient use of surface water.