Faba Bean Agronomic and Crop Physiology Research in Ethiopia

Faba bean is an important pulse crop in terms of protein source, area coverage, and volume of annual production in Ethiopia. The aim of this paper is to assess the agronomic and crop physiology investigations in the past two decades in Ethiopia. The production limiting factors of this crop are low input usage, natural disasters, depletion of macronutrients, and unavailability of essential nutrients. Phosphorus is among the main limiting nutrients in soil systems in Ethiopia. Seed yield and biomass yield of faba bean were increased from 1338 to 1974 kg/ha and from 3124 to 4446 kg/ha when phosphorous was changed from 0 to 52 kg/ha, respectively at Holeta whereas application of 40 kg P ha − 1 resulted in higher grain yield (6323 kg ha−1) and 3303 kg ha−1 at Lemu-Bilbilo and Bore highlands, respectively. The highest grain yield of 32 kg ha−1 was obtained from the application of 92 kg P2O5 ha−1 at Sekela district while application of 46 kg P2O5 ha−1 resulted in a substantial increase in seed yield over unfertilized plots on vertisols of Ambo. On the other hand, the results suggest that using starter nitrogen from 0 to 27 kg/ha has marginally increased faba bean yield but, a farther increase of nitrogen has indicated deteriorate of yield at Arsi zone. Proper plant populations play a crucial role in enhancing faba bean production. Planting faba bean at 30 cm × 15 cm spacing gave the highest grain yield in Duna district while it was 30 × 7.5 cm at vertisols of Ambo University research farm. Significantly higher seed yield (4222 kg/ha) was observed in the 40 cm inter-row spacing as compared to 50 cm inter-row spacing, which gave the lowest seed yield per hectare (3138 kg/ha) on fluvisols of Haramaya University. Intercropping and crop rotation are cropping systems that can increase soil fertility and crop yield. Intercropping of faba bean with barley at Debre Birhan increased land equivalent ratio than both crops when planted as sole. An additional income of 18.5% and 40% was gained than planting sole faba bean and wheat, respectively at Kulumsa. Faba bean can fix about 69 kg/ha nitrogen in Northern Ethiopia. Generally, the current review results showed that only limited studies in organic and bio fertilizer, plant density, and cropping systems were done on faba bean in Ethiopia. Hence, studies regarding soil acidity, organic fertilizer, and secondary plus micronutrient impacts on faba bean production and productivity along soil types and weather conditions need great attention in the future in Ethiopia.

Effect of drought stress on crop physiology: A mini-review

Global climate change, in the form of increasing temperature and fluctuating soil moisture conditions including drought stress, is projected to decrease the crop physiology of food crops over the next 50 years. Drought stress is an effect of considered as the lowering in the rate of respiration or decrease in the level of photosynthesis. This mini-review tells us the latest information about the drought stress and its effect on the growth of the plant with relation to photosynthesis and water and the mechanism of adaptation. There are numerous ways of the mechanism of adaptation that allows the plant to tolerate the drought stress condition. This mini-review we can prove the statement of different authors on the tolerance of drought stress and the slight changes in the environmental conditions may lead to the fast flexibility of the cell metabolism is the first and main step in the avoidance of drought stress.

Effect of Different Rates of Nitrogen Fertilization on Crop Yield, Soil Properties and Leaf Physiological Attributes in Banana Under Subtropical Regions of China

Excessive nitrogen (N) application is widespread in Southern China. The effects of N fertilization on soil properties and crop physiology are poorly understood in tropical red loam soil. We conducted a field experiment to evaluate the effect of nitrogen fertilization rates on physiological attributes (chlorophyll, plant metabolic enzymes, soluble matters) on banana leaves, soil properties (soil enzymes, soil organic matter (SOM), soil available nutrients) as well as banana crop yield in a subtropical region of southern China. The N rates tested were 0 (N0), 145 (N145), 248 (N248), 352 (N352), 414 (NFT), and 455 (N455) g N per plant. The correlations among soil factors, leaf physiological factors and crop yield were evaluated. The results indiated that the high rates of N fertilization (NFT and N455) significantly decreased soil available potassium (K) content, available phosphorus (P) content, glutamine synthetase (GS) activity, and soluble protein and sugar contents compared with lower N rates. The N352 treatment had the highest crop yields compared with higher N rates treatments, followed by the N455 treatment. However, there were no significant differences in crop yields among N fertilization treatments. Factor analysis showed that the N352 treatment had the highest integrated score for soil and leaf physiological factors among all treatments. Moreover, the N352 treatment was the most effective in improving carbon and nitrogen metabolism in banana. Crop yield was significantly and positively linearly correlated with the integrated score (r = 0.823, p < 0.05). Path analysis revealed that invertase, SOM and sucrose synthase (SS) had a strong positive effect on banana yield. Canonical correspondence analysis (CCA) suggested that available K, invertase, acid phosphatase and available P were the most important factors impacting leaf physiological attributes. Cluster analysis demonstrated distinct differences in N application treatment related to variations in soil and leaf factors. This study suggested that excessive N fertilization had a negative effect on soil fertility, crop physiology and yield. The lower N rates were more effective in improving crop yield than higher rates of N fertilization. The N rate of 352 g N per plant (N352) was recommended to reduce excess N input while maintaining the higher yield for local farmers’ banana planting.

Assessing the evolution of wheat grain traits during the last 166 years using archived samples

The current study focuses on yield and nutritional quality changes of wheat grain over the last 166 years. It is based on wheat grain quality analyses carried out on samples collected between 1850 and 2016. Samples were obtained from the Broadbalk Continuous Wheat Experiment (UK) and from herbaria from 16 different countries around the world. Our study showed that, together with an increase in carbohydrate content, an impoverishment of mineral composition and protein content occurred. The imbalance in carbohydrate/protein content was specially marked after the 1960’s, coinciding with strong increases in ambient [CO2] and temperature and the introduction of progressively shorter straw varieties. The implications of altered crop physiology are discussed.