Tuber Dry-matter Percentage Research Articles

Reduced P fertilization improves Fe and Zn uptake in potato when inoculated with AMF in P, Fe and Zn deficient soil

Mycorrhiza fungi can use as an efficient resource to increase the efficiency of potato nutrients use, especially phosphorus (P) and nitrogen (N) to achieve sustainable production and protecting the environment and human health. This experiment conducted to study the interaction of P levels and mycorrhiza fungi on absorption of elements and qualitative and quantitative yields of potato under field conditions. Factors including inoculation of mycorrhiza fungi (Rhizophagus irregularis and Glomus mosseae and non-inoculation) and the amount of P (0, 28, 57, 86 and 115 Kg ha−1 P according to H2PO−4, equivalent 0, 25, 50, 75 and 100 percent of P recommended, respectively), with three replications in years 2015 and 2016 at Agriculture and Natural Resource Research Center of Hamadan. The results showed that the maximum of P in tubers (0.351%) and leaves (0.364%), Zn in tuber (24.4 ppm) and leaves (43.9 ppm) and tuber dry matter percentage (24.1%) achieved under inoculation with Rhizophagus irregularis and using of 75% of recommended Phosphorus. Maximum tubers number per plant (7.2) obtained in inoculation with G. mosseae and using of 100% recommended P. Highest tubers weight per plant (898 g) and tuber yield (47.9 ton ha−1) were achieved under inoculation with G. mosseae and using of 75% of recommended P. Both species of mycorrhiza at all levels of P did not show significant difference. The P 75% and 100% under mycorrhizal inoculation treatment did not show significant difference. Highest nitrate percentage in tuber dry matter (136 ppm) and lowest amount of all traits were under non-inoculation along with no application of P. Inoculation treatment with mycorrhizal fungi significantly increased the average weight of tuber compared to non-inoculated treatment. Generally, the use of mycorrhizal fungi at low levels of P was more efficient on all studied traits compared to high levels of P. Given that, there was no significant difference between 75% and 100% P under inoculation with two species of mycorrhiza, provided this conclusion that applying mycorrhizal fungi can reduce agricultural phosphorus consumption without significant decrease in yield.

Potato response to silicone compounds (micro and nanoparticles) and potassium as affected by salinity stress

Salinity of irrigation water is an important limitation factor in crop production such as potato worldwide. Foliar application of anti-stress compounds containing mineral nutrients is one of the possible solutions for salinity mitigation. In this field experiment the effects of silicone compounds on potato (cv. Agria) performance was studied as a split plot based on randomised complete block design with three replications at Ferdowsi University of Mashhad, Iran, during 2016 cropping season. Treatments included irrigation salinity [0.3 (non-stress), 5, 8 and 12 dS.m–1] and foliar application of potassium sulphate (1000 ppm), sodium silicate nanoparticles (400 ppm) and silica (1000 ppm). Results indicated that salinity decreased transpiration rate, stomatal conductance, quantum yield of PSΙΙ, membrane stability index, carotenoids, tuber number per plant and tuber yield while it improved water use efficiency and tuber dry matter percentage. Foliar application of anti-stress compounds positively affected quantum yield of PSΙΙ, carotenoids content, DPPH radical scavenging activity, tuber number per plant, tuber yield and tuber dry matter percentage. Although, application of all compounds improved most biochemical and photosynthetic traits, but ameliorative effect of the two silicon compounds, especially sodium silicate nanoparticles was more evident. It seems that silicon application could be an effective strategy in reducing salinity effects and its efficiency will be increased when is used as nanoparticles.

Impact of Foliar Application with Salicylic Acid on Growth and Yield of Potato (Solanum tuberosum L.) under Different Irrigation Water Quantity

Two field experiments were carried out in the Experimental Station, Faculty of Agriculture, Mansoura University in the two summer seasons of 2014 and 2015 to study the effect irrigation water quantity and foliar application with salicylic acid on growth and yield of potato cv. Spunta grown under clay loamy soil conditions using drip irrigation system. The experiment layout was split plot in based on complete randomized block design with three replications. Quantity of irrigation water (700, 1000 and 1300 m3/ fed.) were present in the main plots, while foliar application with salicylic acid (0.0, 0.1, 0.2 and 0.3 g /litter.) were assigned in the sub plots. The results indicated that increasing water quantity up to1300 m3/ fed. led to a significant increase of vegetative growth parameters ( Plant height, leaves number, leaves area, number of main stem and foliage fresh weight per plant), leaves chemical composition (N, P, K, chlorophyll a, chlorophyll b and carotenoids), Tubers yield and its physical quality (tubers weight and number per plant, marketable and total yield), Tubers chemical quality ( Vit. C, TSS, N, P and K) and plant water relations (Relative water content). On contrary, foliage dry matter percentage, tuber dry matter percentage, hardness, density, electrolyte leakage and water use efficiency were decreased. With respect to the effect of foliar application of salicylic acid, the data exhibited that, the mentioned characters were increased compared to untreated plants except electrolyte leakage. The interaction between irrigation water quantity and spraying salicylic acid showed that the combination which consist of 1300 m3/ fed. and 0.2 g/l salicylic acid gave the highest values for most effective previous parameters.

Effect of Nitrogen Rate on Growth, Yield, Economics and Crisps Quality of Indian Potato Processing Cultivars

A field study was conducted during 2000–2001 and 2001–2002 at the Central Potato Research Institute Campus, Modipuram, India, in order to increasing the processing-grade tuber yield of India’s first ever developed processing potato cultivars, Kufri Chipsona-1 and Kufri Chipsona-2. Tuber yield and post-harvest quality characteristics were evaluated in response to five N levels (0, 90, 180, 270 and 360 kg N ha-1). The crop growth traits (stem number, plant height and compound leaf number) responded positively to N application, whereas the effect of N fertilization on processing-grade tuber number, total tuber number per ha and tuber number per plant was quadratic. There was a steady increase in tuber weight per plant, processing-grade tuber yield, total tuber yield and biomass yield in response to N application. Kufri Chipsona-1 produced a 23.6% higher tuber yield per plant than Kufri Chipsona-2. Agronomic N use efficiency decreased linearly with increased N doses. Specific gravity and tuber dry matter percentage responded positively to N application, while crisps colour (at harvest and after storage) and reducing sugars remained unaffected. Cultivar was the major factor that influenced the tuber quality parameters (specific gravity, crisps colour). Higher values of these quality traits were observed in Kufri Chipsona-2 as compared to Kufri Chipsona-1. Net income and benefit cost ratio (B:C) indicated that Chipsona cultivars should be fertilized with 270 kg N ha-1 for realizing higher processing-grade yields and desirable quality tubers.

Influence of Source and Time of Potassium Application on Potato Growth, Yield, Economics and Crisp Quality

Field studies were conducted at the Central Potato Research Institute Campus, Modipuram (India), during two seasons (2003–2004 and 2004–2005), with two processing cultivars (cvs Kufri Chipsona-1 and Kufri Chipsona-2) and nine combinations of potassium source (K-chloride, K-sulphate and K-nitrate) and time of K application (basal dressing, split application and split application + foliar spray) to investigate their effect on tuber yield and processing attributes for crisp production under subtropical conditions. Yearly variations were observed for most of the variables studied. Between cultivars, the tuber and biomass yield was higher in cv. Kufri Chipsona-1, whereas specific gravity, tuber dry-matter percentage and crisp recovery were higher in cv. Kufri Chipsona-2. Stem number, plant height and compound leaf number were not influenced by sources of K fertilizer or application time. Processing-grade tuber yield, total tuber yield and biomass yield were statistically similar for K-chloride and K-sulphate and lower for K-nitrate. K sources affected both specific gravity and tuber dry-matter percentage significantly; K-sulphate and K-nitrate gave significantly higher values than K-chloride. The application time had no significant effect on processing grade and total tuber yield or on tuber specific gravity and dry-matter percentage. Values for crisp colour and reducing sugars were within the acceptable range for all treatments. Crisp yields were calculated to be highest and oil percentage of the crisps to be lowest when K-sulphate was applied as K fertilizer. Net income and benefit:cost ratio were highest for K-chloride followed by K-sulphate and lowest for K-nitrate. The study suggests that for crisping potatoes, K-sulphate is more suited than K-chloride, as it not only increased tuber dry-matter percentage and crisp yield, but also decreased crisp oil percentage.

Reaction of potatoes to calcium and phosphate levels as affected by wind

In an attempt to increase the number of mini tubers produced per potato plant, the effect of calcium and phosphorus nutrition was investigated. It is believed that high phosphorus (P) and low calcium (Ca) levels stimulate tuberization. Three nutrient solution treatments were used in this study; a well-balanced control, a Ca-poor solution and a nutrient solution with a relatively high level of P. These were applied at pH levels of 6.0 and 4.6, growing ‘Van der plank’ potatoes under greenhouse conditions. Air from the ventilation system entered the greenhouse from a basement, moving upwards at the sides. Two pots were used as a split plot experimental unit, one pot at the windy side and the other next to it at the wind-protected inside. Three replications were used. Single buds, removed from seed tuber tissue were used to produce homogeneous plants, raised in seedling trays, filled with a vermiculite/pine-bark mix as medium. After two weeks, the single stemmed plants were transplanted into Mitcherlich pots, filled with five litres of sterilised river sand. Standard disease and pest control measures were applied and the potatoes were harvested 54 days after transplanting. The low Ca treatment did not significantly affect total tuber mass, tuber numbers or tuber dry matter percentage, not even at the low pH level. The lack of Ca reaction may be due to the fact that the pH in the root zone increased since an ammonium-free nutrient solution was used or due to the mild growing conditions. In contrast to the reported increased number of tubers when P was applied to soil at extremely high levels, addition of P beyond the optimum level reduced the number of tubers per plant but significantly increased tuber size. Of interest was the fact that foliage and tuber yields were significantly reduced by wind at the high P nutrient levels with no effect at the low Ca level.

Aspects of nitrogen fertilizer rate on tuber dry-matter content of potato cv. Record

Effects of three rates of fertilizer nitrogen, viz. 80, 160 and 240 kg N/ha, on tuber yield and dry-matter percentage in potato cv. Record were compared in two experiments. Crop nitrogen uptake increased with application rate but total uptake differed between experiments. Tuber yield was highest following application of 160 or 240 kg N/ha but differences between these two rates were not significant. Tuber dry-matter percentage was reduced in one experiment with increasing nitrogen rate, but in the second experiment final dry- matter percentage was highest following application of 240 kg N/ha. In all treatments, positive linear relationships were found between dry matter percentage and mean fresh weight of tubers >30 mm, but within experiments, the regression coefficients were generally reduced by increased crop nitrogen uptake.

Effects of physiological age and floating plastic film on tuber dry-matter percentage of potatoes, cv. Record

Two experiments investigated the effects of five physilogical ages with and without a floating plastic film on the growth, yield and tuber dry-matter percentage of cv. Record. Samples were taken over a period that represented the early range of harvest dates used in crops destined for crisp manufacture. Plastic film increased final tuber numbers in one experiment but otherwise tuber numbers were not affected by treatments. Tuber yield was incrased by plastic film until August and by advancing physiological age until early July. Within each experiment, tuber drymatter percentage was largely a function of yield. During the main period of tuber bulking, there was a linear relationship between tuber dry-matter percentage and the mean fresh weight of tubers >30 mm when the data from both experiments were combined.

Investigations of Source-Sink Relations in Cassava Using Reciprocal Grafting

SUMMARYSource-sink relations in cassava were investigated following reciprocal grafting among three cultivars of different yield groups. Both rootstock and scion had significant effects on net assimilation rate and tuber yield, demonstrating that both sink capacity and source activity are important in achieving maximum tuber yield. The scion had no effect on tuber dry matter percentage and starch content of the grafts but the hydrocyanic acid content of the tuber was significantly influenced by both rootstock and scion.

Processing potential of potato cultivars at early harvests

Assessments were made in three seasons of yields and tuber dry-matter percentages at harvests from June to early August in a range of cultivars gorwn at a coastal site in south-west Wales. Lareg differences in tuber dry-matter percentage were found between cultivars within seasons and also at similar dates between seasons.The cultivar Home Guard produced consistently high dry-matter percentages each year in the period from late June to early August but cv. Redord achieved similar or higher dry-matter contents after mid-Julyl. Most other cultivars produced lower dry matter percentages throughout the sampling period. The potential for the use of early maturing cultivars in late June and July for processing into crisps is discussed.

Effects of defoliation and time of harvest on tuber dry-matter percentage of Pentland Crown Potatoes

Two experiments are reported which investigated the effects of time and method of crop defoliation and of extending the interval between defoliation and harvest on the relationship between dry-matter percentage and tuber size in Pentland Crown potatoes.Differences in average tuber dry-matter content between seasons and treatments were large, but the relationship between tuber dry-matter percentage and tuber size was always negatively quadratic. The dry-matter content of tubers of all sizes invariably decreased after defoliation, by about 0·6 % on average for each week that harvest was delayed in 1983 and 0·3 % in 1984. The largest decrease was from 22·7 to 16·7 % over the 10-week period following mechanical defoliation in mid-August 1983. In 1984, chemical defoliation in mid-August gave a smaller decrease than the mechanical method (0·25 and 0·38%/week) but their effects were similar when carried out in mid-September. Water uptake was the main factor responsible for the decrease because evidence showed that fresh weights of tubers increased proportionally following defoliation whilst dry weights remained virtually constant.Natural senescence was late in both seasons experiments so that the crops foliage was still mostly alive when defoliation occurred, even in September and early October. Thus, the relatively large effects of late defoliation may have been greater than might be expected where haulm senescence is already well advanced by this time and water uptake has almost ceased. Nevertheless, the decline in dry-matter percentage which may occur between defoliation and harvest can be extremely important where potatoes for processing are concerned. It could make them unacceptable for particular outlets and should be considered when defoliation and harvesting programmes are planned.

Growth, Partitioning, and Harvest Index of Tuber-Bearing Solanum Genotypes Grown in Two Contrasting Peruvian Environments

Ten Solanum potato genotypes, including four primitive species and six hybrids, were grown to maturity near 230 and 3273 meters in elevation at two sites, Coast and Sierra, in Peru. Growth data, with emphasis upon tubers and leaves, were collected periodically to analyze the plant components which differed in these contrasting environments. Nine of the Solanum species/cultivars effectively partitioned dry matter into tubers with values reaching 73 to 85% of the total plant at mature harvest in the Sierra but dropping to 33 to 75% on the Coast. These harvest index differences were, however, accompanied by no consistent changes in total leaf area, specific leaf area, nor number of tuber initiated. Consistent differences did occur in having shorter plants in the Sierra and an increased tuber dry matter percentage, 20 to 28%, in the Sierra compared to 14 to 21% on the Coast. Linear relationships exist between plant tuber harvest index versus tuber yield and versus total plant dry matter on both the Coast and in the Sierra.

Effects of Ozone and Sulfur Dioxide on Tuber Yield and Quality of Potatoes

AbstractAir pollution injury of the potato plant (Solanum tuberosum L.) has been documented previously, but potato yield losses have not been estimated in replicated experiments having controlled exposures to ozone (O3) and sulfur dioxide (SO2) A controlled‐environment study involving the speckle‐leaf‐sensitive cultivar ‘Centennial Russet’ was conducted to examine the effects of chronic exposure to O3 and SO2 on plant growth and tuber yield and quality.Ozone, at the highest seasonal dose (44.2 ppm‐h), reduced leaf dry weight 48%, root dry weight 58%, tuber number 38%, and total tuber yield 45%. Lower exposures affected these parameters in linear proportion to the O3 dose. Mean stem (minus leaves) dry weight, tuber dry weight, tuber dry matter percentage, partitioning of dry matter to tubers, and tuber sugar concentrations were not affected. Tuber N concentration increased linearly by up to 21% as the O3 dose increased. Plants grown outside of chambers in ambient air showed effects consistent with results obtained within the chambers. The plants grown outside received a total seasonal O3 dose of 50.4 ppm‐h and produced 58% less tuber yield than filtered air control plants.Plant responses to SO2 exposure were much less pronounced than their responses to exposure to O3. However, leaf symptom development in O3‐treated plants was markedly intensified by the presence of SO2. Small reductions in tuber yield and mean tuber size, but not in tuber number, were observed in SO2‐treated plants. Tuber N concentration increased slightly in SO2‐treated plants.A significant O3 × SO2 interaction was observed in the case of tuber N concentration only; SO2 accentuated the O3‐induced increase in N content.

Effects of variety and date of harvest on the tuber dry-matter percentage of potatoes

SummaryUsing data from four field experiments, comparisons were made between the drymatter percentages of several varieties harvested at different times during the growing season.There were negative quadratic relationships between tuber dry-matter percentage and tuber size in all varieties except Pentland Marble. The dry-matter percentage of particular tuber sizes varied according to the variety and the time of harvest. Failure to recognize the importance of tuber size and the time of harvest may easily distort differences in dry-matter percentage between varieties.There were significant positive correlations between the number of tubers produced by each variety on 25 June and four different variables representing the dry-matter percentage of tubers harvested on 10 September. Varietal maturity, assessed as persistence of the foliage, was not significantly correlated with any tuber dry-matter percentage variable in September.

Some effects of planting density and variety on the relationship between tuber size and tuber dry-matter percentage in potatoes

SummaryThree experiments are reported which investigated the effects of planting density and variety on the relationship between tuber dry-matter percentage and tuber size. In the first experiment dry-matter determinations were made on samples of tubers less than 3·8 cm and greater than 3·8 cm from different planting densities obtained at eight fortnightly harvests. Standard analysis of variance was used for each harvest date and apart from Maris Piper giving consistently higher dry-matter percentages than Pentland Crown for the same tuber sizes, effects were small and difficult to interpret. The reasons for the problems in interpretation, which were mainly due to differences in tuber size distribution, are discussed.In the second and third experiments the effects of tuber-size distribution were removed by regression analyses of tuber dry-matter percentage on tuber size in definable grades and curves were fitted to the data. These curves revealed that tuber dry-matter percentage tends to show a quadratic response to increasing tuber size and is affected by variety and stem density. The significance of these results is discussed.