Effect of rainwater harvesting with ridge and furrow on yield of potato in semiarid areas
A new planting pattern for potato production in semiarid areas was designed and tested for enhanced tuber yield and for the benefit of collecting rainwater. This pattern comprised two elements: the ridge mulched by plastic film that acts as the runoff area and the furrow as the infiltration basin or planting area. The conventional planting pattern for potato production in semiarid regions of northwestern China is the opposite with mulched ridges for planting and the furrow as an infiltration zone. The purpose of this study was to examine the effect of the ridge with or without mulching on rainwater harvesting and the response in potato yield and to determine the optimal cross-sectional area of the ridge and furrow. A ratio defined as the width of the ridge to the width of the furrow or the planting area was used to evaluate the cross-sectional area. Three ratios of 0.5, 0.75, and 1.0 were tested under the conditions of mulched ridge, bare earth ridge, and no ridge or flat planting, respectively. No matter what ratio used, the width of the planting belt was the same at 0.6 m. The results showed that for tuber yield, the ridge with the plastic mulching was more effective than the bare earth ridge and that the bare earth ridge was better than flat planting. In the mulched ridges, a ridge width of 0.45 m or a ratio of ridge to furrow of 0.75 led to higher yield than that of ridges with a width of 0.3 and 0.6 m. For the bare earth ridges, the yield in the 0.6 m ridge width was higher than that of the other two ridges. Besides improving potato yield, the mulched ridge and furrow planting had the added advantage of collecting considerable rainwater for soil moisture. In addition, the percentage of small-sized potatoes was low. Therefore, we recommend that the mulched ridge with a ridge width of 0.45 m and a furrow width of 0.6 m as a successful method to increase potato yield in semiarid areas where potato production relies totally on rainwater. 
Aspects of the physiological basis of cultivar differences in yield of potato under droughted and irrigated conditions
Comparisons were made between droughted and irrigated crops in two field experiments conducted on cultivars of potato understood to exhibit a range of drought tolerance to identify important physiological attributes for drought tolerance. Drought reduced total dry matter production and tuber yields and increased tuber dry matter concentration. The better yield response of Désirée was due largely to the greater water content of its tubers. There were differences between cultivars in the number of tubers produced per unit area and in 1984 there were differences between treatments.
Functional differences in canopy growth were revealed in differences in the fractions of incident solar radiation which were intercepted.
The effects of drought were proportioned between components of yield, the principal effects being upon interception of solar radiation and on tuber dry matter concentration. Tuber number was an important factor influencing ware yield. 
Effect of drip tape placement depth and irrigation level on yield of potato
Subsurface drip irrigation (SDI) is the most advanced method of irrigation, which enables the application of the small amounts of water to the soil through the drippers placed below the soil surface. One of the most commonly discussed aspects of SDI system is installation depth of drip lateral. Determining the appropriate depth of installation involves consideration of soil structure, texture, and crop’s root development pattern. Site-wise and crop-wise variations of these parameters preclude the possibility of framing general recommendations for installation depths of SDI system. An experiment was conducted on potato (var. Kufri Anand) during October–February for 3 years (2002–2003, 2003–2004 and 2004–2005) to study the effect of depth of placement of drip tape and different levels of irrigation application on potato yield. Drip tapes were buried manually in the middle of different ridges. Tests for uniformity of water application through the SDI system were carried out in the month of October every year. Three different irrigation levels of 60, 80 and 100% of the crop evapotranspiration and five depths of placement of drip tape namely, 0.0, 5.0, 10.0, 15.0 and 20.0 cm were maintained in the study. The coefficient of variation (CV) of flow rates was found 0.046, 0.047 and 0.064 during 2002–2003, 2003–2004 and 2004–2005, respectively. The low CV indicated good performance of the SDI system throughout the cropping season. The values of statistical uniformity (SU) and distribution uniformity (DU) were more than 92.0% during all the three cropping seasons. Soil water distribution at different growth stages of potato under different depths of placement of drip tape for varying irrigation levels was monitored. When drip tape was placed at surface and buried at 5.0 cm soil depth, upward movement of water takes place, 21.5% soil water content was found throughout the crop season of potato. When drip tape was buried 10.0, 15.0 and 20.0 cm below the surface, upward water movement due to capillary forces was not sufficient and soil surface remained relatively dry. 
Yield and Yield Components of Sweet Potato as Influenced by Plant Density: In Adami Tulu Jido Kombolcha District, Central Rift Valley of Ethiopia
Two best performing, morphologically different sweet potato varieties namely, Balella and Bareda, were used to determine optimum spacing between plants and rows in central rift valley of Ethiopia by participating different influential factors from the commencement of the activity. The results indicated that total tuber yield of Balella (644 ±105 q ha-1) performed better with spacing 20 cm x 80 cm than the rest of the treatments i.e., 20 cm x 60 cm (590 ±104 q ha-1) and 50 x 60 cm (522 ±137 q ha-1). But the net marketable yield obtained at spacing combination of 20 cm x 60 cm (590±104 q ha-1) was by far better being followed by 20 cm x 80 cm and 50 cm x 60 cm that gave average yield of 583±82 q ha-1 and 463±93 q ha-1, respectively. Correlation matrix of dependent variables resulted that green top weight was significantly correlated with total and marketable root yield (0.887** and 0.846**, respectively). This indicated that variation in total root yield and marketable root yield was accounted by the linear function of total green top yield r2=78.7 % and r2=71.6%, respectively. For Bareda, 20 cm x 60 cm spacing gave total yield of 409 ± 257 q ha-1 followed by 20 cm x100 cm and 30 cm x 60 cm that gave yield of 347 ±139 q ha-1 and 294 ± 63 q ha-1, respectively. The correlation of green top and total root yield obtained for Bareda was strong and positive (r=0.689**). 
Performance of Potato Varieties for Growth, Yield, Quality and Economics under Different Levels of Nitrogen
Aims: This experiment was conducted to study the performance of different varieties of potato under various nitrogen levels for growth, yield and quality as well as their economics.
Study Design: Sixteen treatment combinations comprising of four varieties (V1-Kufri Jyoti, V2-Kufri Chipsona-2, V3-Kufri Chipsona-1 and V4-Kufri Pushkar) and four nitrogen doses (N1-100 kg/ha, N2-125 kg/ha, N3-150 kg/ha and N4-175 kg/ha). The experiment was laid in Factorial Randomized Block Design with three replications.
Place and Duration of Study: A field experiment was conducted at research field, Department of Vegetable Science College of Horticulture, Mandsaur during rabi season 2010-11.
Methodology: The healthy, uniform size tubers were planted at a spacing of 60×20 cm on 21 October, 2010. Phosphorus (P2O5 80 kg/ha), potassium (K2O 100 kg/ha) and different doses of nitrogen (as per treatment) were provided through Urea, DAP and Muriate of Potash. Full dose of phosphorus, potash and half dose of nitrogen were applied as basal in furrows at the time of planting. While the remaining quantity of nitrogen was applied in two split doses, 1st at first earthing-up and 2nd at second earthing-up (25 and 45 days after planting, respectively). Thereafter recommended package of practices were followed to raise the healthy crop. The crop was harvested on 15 February, 2011.
Results: The findings of present study revealed that among the varieties, Kufri Pushkar recorded maximum yield showing its superior performance over other varieties. With respect to quality attributes, variety Kufri Chipsona-2 exhibited high dry matter content, high starch content and low reducing sugar content which are the desired attributes for processing. Variety Kufri Chipsona-1 and Kufri Jyoti were next to Kufri Chipsona-2. Among the different doses of nitrogen, application of 150 kg N/ha resulted in maximum growth and yield attributes as well as total yield. It has also exhibited better quality parameters except reducing sugar. Combined effect of varieties and nitrogen levels showed highest economic return under application of 150 kg N/ha with variety Kufri Pushkar.
Conclusion: It may be concluded that combination of potato variety Kufri Pushkar along with application of nitrogen 150 kg/ha had proved to be superior over other combinations for growth, yield and economic returns. 
 Tian, Y., Su, D., Li, F. and Li, X., 2003. Effect of rainwater harvesting with ridge and furrow on yield of potato in semiarid areas. Field Crops Research, 84(3), pp.385-391.
 Jefferies, R.A. and MacKerron, D.K.L., 1987. Aspects of the physiological basis of cultivar differences in yield of potato under droughted and irrigated conditions. Potato Research, 30(2), pp.201-217.
 Patel, N. and Rajput, T.B.S., 2007. Effect of drip tape placement depth and irrigation level on yield of potato. Agricultural water management, 88(1-3), pp.209-223.
 Abdissa, T., Chali, A., Tolessa, K., Tadese, F. and Awas, G. (2011) “Yield and Yield Components of Sweet Potato as Influenced by Plant Density: In Adami Tulu Jido Kombolcha District, Central Rift Valley of Ethiopia”, Journal of Experimental Agriculture International, 1(2), pp. 40-48. doi: 10.9734/AJEA/2011/173.
 Jatav, A. S., Kushwah, S. S. and Naruka, I. S. (2017) “Performance of Potato Varieties for Growth, Yield, Quality and Economics under Different Levels of Nitrogen”, Advances in Research, 9(6), pp. 1-9. doi: 10.9734/AIR/2017/33599.