Influencing seed tuber yield of Ranger Russet and Shepody potatoes with gibberellic acid

Freshly-cut seed pieces of the potato cultivars Ranger Russet and Shepody were dipped in 0, 0.5, 1 or 2 mg/1 Gibberellic Acid (GA₃) prior to planting. GA₃ treatments increased stem and tuber numbers per hill of both cultivars and shifted tuber size profile toward the production of more seed-sized (up to 226 g) tubers and fewer large (greater than 340 g) tubers. The effect of GA₃ on reducing average tuber size was similar for the two cultivars. Total tuber yields were not affected. A 2 mg GA₃/1 seed piece dip decreased the yield of US#1 tubers in Ranger Russet primarily due to a significant increase in yield of tubers less than 226 g. Also, yields of culls were greater after a 1 mg GA₃/1 seed piece treatment, suggesting Ranger Russet is sensitive to this concentration of GA₃. One and 2 mg GA₃/1 seed piece dips to Shepody increased yields of tubers less than 113 g by 93% and reduced the yield of tubers greater than 340 g by 25% to 50%. GA₃ at 1 to 2 mg/1 may be useful in the production of seed potatoes with the cultivar Shepody which tends to produce many large tubers.     

Inheritance of tuber shape in cultivated diploid potatoes

The inheritance of tuber shape was studied by developing and/or selecting clones from a cultivated diploid potato breeding program. Progeny analyses indicated that one major gene controls the round and long shapes. Round is dominant over long. The gene symbol Ro, earlier proposed by Masson, is accepted. All three possible genotypes, RoRo, Roro and roro were identified. Ro was found to be linked with I, a previously described gene which controls the expression of anthocyanin in the tuber skin. In nearly all genotypes studied the linkage was in the coupling phase; however, one parent was identified where the linkage was in the repulsion phase. The recombination frequency between Ro and I was found to be approximately 11.8%. The implication of linkage between tuber skin color and shape is discussed.     

Ethylene in a compacted field soil and its effect on growth,tuber quality,and yield of potatoes

Ethylene (C₂H₄) produced by soil microorganisms at concentrations sufficient to affect root development has previously been identified in the gas phase of anaerobic or partially anaerobic soils. This research was initiated to establish the existence of and to determine concentrations of C₂H₄ in soil in relation to matric potential, oxygen (O₂) and compaction, and effects on growth and tuber yield of potatoes (Solanum tuberosum L.). Ethylene initially appeared at the 10-cm depth after 2.5-cm/day increments of water were applied by furrow irrigation for 3 days. Levels of C₂H₄ increased to 18.4 ppm and O₂ decreased to 8% after 12.5 cm of water had been applied in 2.5-cm increments for 5 days. Ethylene was found in two partially compacted plots. High C₂H₄ concentrations and low O₂ levels in the soil atmosphere were associated with reduced top growth, leaf injury, lower tuber quality, and a 20% decrease in potato yields. Since C₂H₄ and low O₂ levels occur simultaneously in soil, further research is needed to identify their individual effects on root and tuber development.     

The effect of green sprouting on yield of early potatoes

Three yield trials of early sizing potato seedlings and varieties were conducted at separate locations over a two-year period in New Brunswick, Canada. Two preplanting treatments of the seed were used: green sprouting for 3 weeks at 65 F (18 C) and check samples from storage at 45 F (7 C). Graded yield results and specific gravity determinations obtained 82 days after planting are presented. A highly significant increase (16–28%) in yield of marketable tubers was obtained from the green sprouted treatments. Higher specific gravities were recorded for 32 of the 43 green sprouted plots over the checks.     

Effect of daminozide on survival,growth and yield of micropropagated potatoes

The effect of daminozide [Butanedioic acid mono (2,2-dimethyl hydrazide)] on growth, field establishment and productivity of micropropagated Kennebec and Russet Burbank potato was studied. Addition of daminozide to the medium significantly reduced stem length ofin vitro propagated plantlets. Optimal dose was 0.6 mg active ingredient per plant. This dose did not significantly alter the number of nodes and leaf area. Three transplanting methods were examined: direct from tissue culture to the field without protection; the same but with a plastic covering for protection; and after 7 days acclimation in a greenhouse but without protection in the field. Stand establishment ranged from 83.3 to 100%. The second transplanting method had the highest percentage establishment for both cultivars. The application of daminozide improved survival for all transplants of Kennebec and the directly planted plantlets of Russet Burbank. Independent of the daminozide treatment, plants of both cultivars hardened in the greenhouse prior to transplanting produced the highest number and yield of tubers. For Russet Burbank, daminozide caused a delay in tuberization but did not affect tuber bulking and haulm growth.     

Influence of pre-sprouting on tuber number,size and yield of King Edward potatoes

Summary Experiments show that sprouting treatment, seed size and spacing affect the number and size of tubers produced. Early sprouting gives fewer sprouts per set and hence plants per hill than late sprouting. The number of tubers produced is directly related to the number of plants. Sets with few sprouts (plants) produce fewer tubers than sets with many sprouts. Small seed produces fewer plants and hence tubers than large seed. The size of the tubers is inversely related to tuber numbers. In 1960 unsprouted seed produced fewer and larger tubers than pre-sprouted seed butPhytophthora infestans was not experienced. Early sprouting, small seed and wide spacing increased tuber size, but early sprouted seed planted closely gives a higher yield of ware than late sprouted seed planted further apart. Pre-sprouting results in earlier emergence and tuber set but does not necessarily increase the yield of ware. If early drought occurs, presprouting may increase the proportion of mishapen tubers.

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Zusammenfassung Versuche haben ergeben, dass Vorkeimung, Gr?sse der Saatknollen und Pflanzabstand die Anzehl und Gr?sse der erzeugten Knollen beeinflussen. Frühkeimung gibt weiiger Triebe je Pflanzknolle und somit Pflanzen je Staude als Sp?tkeimung. Die Anzahl der erzeugten Knollen steht in direktem Verh?ltnis zu der Zahl der Pflanzen, Pflanzknollen mit wenig Trieben (Pflanzen) liefern weniger Knollen als Saatgut mit vielen Trieben. Kleine Saatknollen ergeben weniger Pflanzen und somit Knollen als grosse Saatknollen. Die Gr?sse der Knollen steht in umgekehrtem Verh?ltnis zu der Knollenzahl. Im Jahre 1960 ergaben ungekeimte Saatknollen weniger und gr?ssere Knollen als vorgekeimte Saatknollen, jedoch kam kein Befall vonPhytophthora infestans vor. Durch Frühkeimung, kleine Saatknollen und weiten Pflanzabstand wurde die Knollengr?sse gesteigert; vorgekeimte Saatknollen bei enger Pflanzung ergaben jedoch einen h?heren Ertrag an Verbrauchskartoffeln als sp?tgekeimte, die in gr?sserem Abstand gepflanzt waren. Vorkeimen bewirkt früheren Aufgang und Knollenansatz, erh?ht jedoch nicht unbedingt den Ertrag an Verbrauchskartoffeln. Wenn früh Trockenheit eintritt, kann das Vorkeimen Ursache eines gr?sseren Anteils an missgebildeten Knollen sein.

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Résumé Des essais ont démontré que la prégermination, la grosseur des plants et leur espacement influencent le nombre et la grosseur des tubercules récoltés. Une germination précoce donne moins de pousses par plant, c’est-à-dire moins de plantes par touffe qu’une germination tardive. Le nombre de tubercules obtenus est directement proportionnel au nombre de plantes. Les plants portant peu de pousses (peu de plantes) produisent moins de tubercules que les plants qui présentent des pousses nombreuses. Les petits plants donnent moins de plantes et donc moins de tubercules que les gros plants. La grosseur des tubercules obtenus est indirectement proportionnelle à leur nombre. En 1960, les plants non prégermés produisirent des tubercules moins nombreux et plus gros que les plants prégermés, mais il n’y eut pas d’attaque dePhytophtophthora infestans. La germination précoce, le petit format des plants et leur grand espacement faisaient augmenter la grosseur des tubercules, mais les plants prégermés et plantés et plantés serré donnaient un plus haut rendement en tubercules de consommation que les plants germés tard et espacés davantage. La prégermination occasionne une levée plus précoce et une tubérisation également plus précoce, mais n’augmente pas nécessairement le rendement en tubercules de consommation. En cas de sécheresse au début de saison, la prégermination peut accro?tre le nombre de tubercules difformes.

     

Relationships between stem number,tuber set and yield of Russet Burbank potatoes

Five storage temperatures and three planting dates were used to obtain differences in seed performance. As seed storage temperature increased, average stem number per seed piece significantly increased. Stem number also increased with later planting dates. Germination tests, conducted under controlled temperatures, resulted in a curvilinear response with the least stems per seed piece at 10°C. a maximum stem number at 16°C and a slight decline in number at 21°C. The major effect of planting date was manifested through differences in germinating temperatures which resulted in increased stem number with later plantings. Yield of U.S. No. 1 tubers (5cm or 112 gm minimum) declined significantly as stem number increased. In the first planting, the correlation coefficient between stem number per seed piece and yield was r = ?0.95. Increased stem number and declining yield were attributed to advanced physiological age resulting from exposure to higher temperatures in storage and in the field. As stem number increased with planting date, tuber number also increased. The correlation coefficient between stem and tuber number for the first planting date was r = 0.92. The relationship declined significantly on the third planting date to r = 0.46. From these results it was concluded that economic yields are influenced by stem and tuber number which in turn can be manipulated by control of seed storage temperatures and planting dates.     

Hill to hill variations in tuber yield of potatoes in Alberta

The hill to hill variation in tuber yield and mainstem number was studied on 18 potato farms. There were up to 14-fold differences in the tuber yield per hill among plants of Norland, Russet Burbank, Norchip, Carlton and Alaska Red. The mainstem number was more variable than tuber weight per hill in Norland, Russet Burbank and Alaska Red. However, the opposite was true in Norchip and Carlton. In nearly all comparisons, the number of tubers per hill was less variable than tuber weight and mainstem number per hill. The total variation in tuber weight found in about 50% of the samples could be explained by the variance of hills within rows. Even in samples where an added variance component due to differences among rows was present, relatively more variation occurred within than among rows. The correlation coefficients between the number of mainstems and tuber weight per hill were positive but significant (P&< 0.05) only in Norland and Norchip. The correlation coefficients between the number of mainstems and number of tubers per hill were also positive but slightly higher and significant (P<0.01) in all 5 cultivars. The coefficient of determination values indicated that variation in cut seed piece weight explained only about 10% of the total variation in tuber weight harvested per hill. At a spacing of 30 cm within the row, a major proportion of hill to hill variation in tuber yield had to be explained by factors other than the seed piece weight.     

外源赤霉素对不同磷素水平下胡麻产量形成的调控效应研究

为探究磷素养分和外源赤霉素(GA3)对旱地胡麻干物质积累特征及产量形成的调控效应,采用田间二因素裂区试验设计,研究了不同磷素水平(0、67.5和135 kg P2O5·hm-2)下于现蕾期和盛花期不喷和喷施15 mg·L-1、30 mg·L-1 GA3对胡麻干物质积累规律,花前、花后转运特征及产量的影响.结果表明:磷素...     

Influence of early haulm killing of seed crops on subsequent sprouting,physiological ageing and tuber yield

Summary The production of healthy and high yielding seed potatoes is closely related to the control of virus diseases and to other cultural practices, like those modifying the physiological age of tubers. Seed crops from cv. Bonaerense La Ballenera MAA, were defoliated early in 3 seasons, 1983/84, 84/85 and 85/86. After harvest, the seed tubers were stored in heaps in the field and, later, their sprouting capacity and physiological age, and their tuber yield were evaluated. Results showed that early haulm killing did not affect these variables nor diminish the quality of the seed potatoes obtained.     

Effect of water stress during tuber formation on subsequent growth and internal defects in Russet Burbank potatoes

A study was conducted to evaluate the effect of early season water stress on yield, quality, and internal disorders of Russet Burbank potatoes grown on sandy soil. There were trends for decreased internal disorders early in the season as the water stress increased. However, these trends did not persist. At harvest in mid-September there was no consistent association between internal disorders of U.S. No. 1 tubers and early season irrigation treatments. Yield, grade, and specific gravity were affected to a minor degree by the treatments.