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Sums of squares for the effects of seed-tuber age and time after planting on growth indices of Russet Burbank potato'
Source publication
Four physiological ages of potato (Solanum tuberosum L. 'Russet Burbank') seed-tubers were produced by varying the time of storage at 15 °C. Age was quantified as the accumulated degree-days (dd) above 4 °C over the 199-d storage interval, and plant emergence and establishment were then modelled in controlled environment studies. As age advanced, t...
Similar publications
Potato is an important food crop with high water-use-efficiency but low drought tolerance. The bottleneck in drought tolerance breeding is phenotyping in managed field environments. Fundamental research on drought tolerance is predominantly done in container-based test systems in controlled environments. However, the portability of results from the...
Citations
... During later phases, however, the effects of storage at 4 to 10 °C were usually inconsistent across sites. The finding that physiological age has more pronounced influences on the early stages of plant growth compared to the late stages aligns with previous findings (Perennec and Madec 1980;Van der Zaag and Van Loon 1987;Benz and Fahem 1988;Knowles and Botar 1991;Van Ittersum 1993), indicating that early crop performance is more prominently governed by the inherent properties of the seed tubers, while the impact of environmental conditions becomes more predominant as the growing season progresses. ...
The physiological age of potato seed tubers influences the subsequent field performance of the crop, conditioning its growth and development. This study investigates the effects of the physiological age of seed tubers on the field performance of four contrasting, currently widely grown cultivars (Agria, Festien, Innovator, Lady Claire) across three sites in the Netherlands over 3 years (Cycles 1—3). Seed tubers were produced annually at a single site under uniform conditions, with variations in physiological age induced by applying different storage temperatures (4, 7, 10, and/or 17 °C). Our previous study revealed varying effects of storage temperature on sprouting behaviour among cultivars, suggesting different rates of ageing. After completing the storage season, in the current study these seed tubers were planted in the field and subsequent crop performance was thoroughly phenotyped. Cultivar-specific effects of storage temperature were evident during early growth stages and when seed tubers were stored at 17 °C in Cycle 3. However, within the storage temperature range of 4 to 10 °C, the influence of storage temperatures was small or inconsistent. Overall, effects on canopy cover, stem and tuber number, yield and quality, and tuber yield explanatory variables were limited. The outcomes suggest that while very high storage temperatures should be avoided in regions with long crop cycles, stringent cold storage regimes are unnecessary to achieve optimal growth vigour in potato seed tubers of the studied cultivars in a temperate climate.
... For these reasons, improving yam agricultural productivity is significantly hampered by the lack of access to high-quality planting material, which is often cited as the most pressing challenge . Worldwide, seed production systems have significantly improved the production of potatoes (Solanum tuberosum), mainly through better control of virus transmission and improved earliness and homogeneity of emergence (Forbes et al., 2020;Knowles & Botar, 2011). Despite compelling evidence, the actual cost of using heterogenous yam seed tubers, or, in simpler terms, the anticipated advantage of using better planting materials, remains uncertain. ...
Societal Impact Statement
Yam is a major tropical root crop and a staple food for millions of people in West Africa. The model used in this study shows that promoting the use of improved seed tubers would help increase yields and profitability for farmers. This could lead to improved food security, increased income and higher standards of living. Additionally, the model serves as a useful decision‐support tool for farmers and technicians to choose, depending on the species, the optimum seed‐tuber weight and planting date. This study provides agronomic arguments to justify investments in the improvement of yam planting materials in West Africa.
Summary
Yam ( Dioscorea spp.) is a major tropical root crop, grown mainly in West Africa using traditional extensive techniques. Farmers typically reuse seed tubers by setting aside up to 30% of their production for the next season, leading to high planting material variability that affects yields. Several initiatives aim to promote the use of improved seed tubers. However, to help their adoption, it is necessary to quantify the agronomic and economic advantages.
To address this, a model for individual plant growth and development was developed based on six experiments in Benin from 2007 to 2009. This model simulates the combined effect of emergence (through photoperiod and temperature) and seed‐tuber weight on yam plant growth and development. Its predictions were highly correlated with observed plant tuber yield ( R ² > 0.83).
Results highlight the crucial role of key processes such as seed‐tuber physiological age and photoperiod sensitivity. The study shows that for the traditional planting dates, the use of improved planting material could lead to a yield increase of 22%–27% and a gain in profitability of 30% and 40% for Dioscorea alata and Dioscorea rotundata , respectively. The model proved to be a useful decision‐support tool for choosing an optimum seed‐tuber weight, depending on the species and the planting date.
This study validates investments in yam seed systems in West Africa. However, beyond seed size and health, other factors such as dormancy, storage time and their management need to be considered to address emergence heterogeneity and its impact on yield.
... Elevated temperature and prolonged storage (increased chronological age) are extensively described as physiological ageing factors (Krijthe 1962;Struik & Wiersema 1999). For this reason, many studies of seed potato physiological age (O'Brien et al. 1983;Allen & O'Brien 1986;Knowles & Botar 1991;Struik et al. 2006) have focused on these two aspects of the storage phase which may be expressed as accumulated temperature units (or thermal time,°Cd). Furthermore, handling and pretreatment prior to planting (e.g. ...
... In many places (Knowles & Botar 1991) including Canterbury, New Zealand, seed potatoes are stored in a cool store (2-4°C) for most of the storage phase before they are planted in the field in spring (e.g. mid-October in Canterbury). ...
... The current work indicates that the total sum of temperature above a base temperature during the whole storage period (Knowles & Botar 1991;Knowles & Knowles 2006;Blauer et al. 2013) was not an accurate way to assess the physiological state of the seed potato. The effects of physiological age on the number of stems, size distribution and yield advocated in many studies (Allen & O'Brien 1986;Van Loon 1987) were unresponsive to the sum of°Cd prior to sprouting (Early treatments) applied to 'Bondi' and 'Fraser' seed potatoes. ...
After seed potatoes (Solanum tuberosum L.) are harvested, they may be stored in sheds, in low temperature coolers or left un-lifted in the ground. This research describes the response of tuber yield and distribution (formed by the weight grade of each potato) of ‘Bondi’ and ‘Fraser’ crops planted from seed potatoes at different physiological ages generated from different combinations of these storage regimes applied in the Early and Late phases of storage. De-sprouting half of the potatoes prior to planting was used to accelerate the rate of physiological ageing, synchronise the planting material and increase the range of treatments. Total yield and number of potatoes produced were unaffected by any of the storage treatments and reflected a constant pattern of canopy development, radiation use efficiency and harvest index. The largest tubers were attained by higher rates of tuber growth which was inversely related to the number of stems per plant.
... Temperature sum accumulation increases the physiological age of seed potato (O'Brien, Jones, Allen, & Raouf, 1986). Studies show that physiologically older seed potatoes emerge more quickly than the younger ones (O'Brien et al., 1983;Bodlaender & Marinus, 1987;Van der Zaag & Van Loon, 1987;Knowles & Botar, 1991;Jenkins, Gillison, & Alsaidi, 1993;Essah & Honeycutt, 2004;Eremeev et al., 2008). Particularly in short growing season production areas, the quick emergence of seed potatoes accelerates early development of potato growth. ...
In the present study effects of production history on tuber sprout, root, stem development and crop yield of seed potato cultivars Fambo and Van Gogh were investigated in the High Grade Area of Finland (64.9 N, 25.4 E). The haulms of seed potatoes were destroyed at the time of flowering (50 days after planting, DAP), three weeks after flowering (75 DAP) and as a control the haulm was left to natural death until harvest (95 DAP). The temperature sum accumulation of the seed potatoes was recorded for the growing season and storage period. In addition, the use of plant hormone gibberellic acid (GA) in sprout control was also investigated. The results indicated that cultivar properties had a greater effect on the sprouting and crop yield of seed potatoes than production-phased haulm killing or temperature sum accumulation. Haulm killing carried out at three weeks after flowering (75 DAP) accelerated the emergence of both cultivars significantly compared to killing at 50 DAP or 95 DAP. Gibberellic acid (GA) treatments significantly increased the number of sprouts and at lower concentration (100 mM) GA increased the number of tubers in the cultivar Fambo. Thus, the timing of haulm killing and in the case of Fambo, GA treatment influenced the characteristics of seed potatoes produced in the present study, revealing methods to improve seed potato production in the northern latitudes.
... Although there is a growing literature on the physiological age of seed tubers, the application for potato management is currently imprecise. In general, advancing seed-potato age affects crop yield, but the actual effect depends not only on the variety (van der Zaag & van Loon, 1987), but also on the field conditions (Knowles & Botar, 1991;Caldiz et al., 1998), cropping systems (Karalus & Rauber, 1997), and managerial skills. ...
For earlier potato yield formation we used pre-sprouting and thermal treatment which both add to the physiological age of
potato. At the same time, pre-sprouting is a very time- and energy-consuming procedure. We investigated if thermal
treatment could replace pre-sprouting and how it affects the growth and development of potato haulms and tubers. For that
purpose an experiment was conducted in 2000�2002 to examine the opportunities for growing potatoes by using different
methods of pre-planting treatment of seed tubers.
Early, middle and late maturing potato varieties (two Estonian varieties and one Latvian) were used, each being
subdivided into three variant categories: untreated, thermal shock and pre-sprouting.
The experiment indicated that one or the other of thermal shock or pre-sprouting shortened the time to emergence by up
to 10 days. With pre-sprouting, the formation of tubers started as soon as 45 days after planting and with thermal shock 50
days after planting, i.e., 5�10 days earlier than in the untreated variant.
Thermal shock of seed tubers had the greatest effect on the number of tubers per plant, while pre-sprouting increased the
average weight of tubers.
Both pre-sprouting and thermal shock had a strong effect on the weight of the haulms in varieties with a longer growth
period.
... sprouted seed tubers to utilize the short growing season more efficiently than plants from non-sprouted seed tubers. Although O'Brien et aL (1983) and Knowles and Botar (1991) observed green-sprouting to increase yields at early harvest, but decrease them later, they acknowledged that absence of water stress would minimize the effects of green-sprouting on final yield. The accelerated emergence from green-sprouted seed usually aids the plant's growth because the vegetative period is advanced, thereby allowing the plant to benefit from more favorable water supply and higher light intensity earlier in the season (O'Brien et al. 1983). ...
Management practices that accelerate crop development and allow earlier harvest would be beneficial in short-season potato
(Solanum tuberosum L.) production areas. Yield and quality of the potato cultivar ‘Russet Burbank’ were evaluated in a 2-yr study in northern
Maine to determine effects of soil tillage and seedsprouting treatments designed to dry soil early in the spring and hasten
seed emergence. The tillage treatments, consisting of fall raised bed (RB), fall ridge till (RT), and spring chisel plow (CH),
were tested in combination with green-sprouted and non-sprouted seed tubers on a Caribou gravelly loam (coarse-loamy, mixed,
frigid,Typic Haplorthod). Plants from green-sprouted seed emerged earlier than from non-sprouted seed tubers (87%-96% vs 21%-37%, respectively, at
18 days after planting [DAP] in 2000; and 73%-88% vs 18%-23%, respectively, at 20 DAP in 2001). Green-sprouted seed tubers
in RB yielded 4.6 to 5.9 T ha-1 more than nonsprouted seed tubers in RB. However, non-sprouted seed tubers yielded higher than green-sprouted seed tubers
in RT by 2.9 to 4.2 T ha-1 and in CH by 1.1 to 4.1 T ha-1. Similarly, green-sprouted seed tubers in RB and nonsprouted seed tubers in RT and CH produced higher marketable yield, greater
tuber length, and greater tuber diameter than the corresponding seed-sprouting treatment. In the comparatively wetter year
(2000), the use of green-sprouted seed tubers in RB significantly increased total and marketable yields, and produced longer
and larger tubers than all other treatments. However, in 2001 (relatively dry year), yield and quality from green-sprouted
seed tubers in RB did not differ from non-sprouted seed in RT or CH. Green-sprouted seed produced fewer sunburned and rotten
tubers, but more misshapen tubers than non-sprouted seed in RB tillage. The technique of producing Russet Burbank potatoes
in raised beds is a promising system in regions with short growing seasons for enhancing early soil drainage during spring
and improving soil water retention during critical periods of crop growth and development.
Las práctices de manejo que aceleran el desarrollo del cultivo y permiten una cosecha temprana serían beneficiosas en las
áreas de producción de papa (Solanum tuberosum L.) de ciclo corto. Se evaluó el rendimiento y calidad del cultivar de papa ‘Russet Burbank’, en un estudio de dos anos en
el norte de Maine para determinar los efectos del tipo de labranza, y de brotamiento diseñados para suelo seco en primavera
y para acelerar la emergencia. Los tratamientos de labranza consistieron en: a) camellones levantados con superficie plana
y mas ancha que lo acostumbrado, construidos en el otoño (RB), camellones estandar hechos con cultivadora construidos en el
invierno (RT) y camellones estandar hechos con un implemento llamado “chisel plow” construídos en la primavera antes de la
siembra (CH). Estos tratamientos fueron probados en combinación con el uso de semilla de tubérculos con brotes verdes y semilla
no brotada, en suelos arcillo-arenosos tipo Caribou (mezcla arcilla y arena gruesa, glacial,Hoplorthod típico). Las plantas provenientes de tubérculos brotados emergieron antes que las de tubérculos no brotados (87%-96% vs 21%-37%
respectivamente, 18 días después de la siembra [DAP], en el 2000 y 73%-88% vs 18%-23% respectivamente a los 20 días después
de la siembra en el 2001). Semilla brotada en RB rindió 4.6 a 5.9 ton/ha-1 más que la semilla no brotada. Sin embargo, semilla no brotada rindió 2.9 a 4.2 ton/ha-1 más que la semilla brotada en RT. Similarmente, semilla brotada en RB y no brotada en RT y CH produjo mayor rendimiento comercial,
tubérculos más alargados y mayor diámetro de tubérculo que el correspondiente tratamiento con semilla brotada. En el ano comparativamente
más húmedo (2000), el uso de semilla brotada en RB incrementó significativamente el rendimiento total y comercial y produjo
tubérculos más largos y mas grandes que en los otros tratamientos. Sin embargo, en el año 2001 (relativamente ano seco), el
rendimiento y calidad de la semilla brotada en RB no se diferenció de la de semilla no brotada en RT o CH. La semilla brotada
produjo menos tubérculos danados por el sol y menos podridos, pero mas tubérculos deformes que los de semilla no brotada en
RB. La técnica de producir papas Russet Burbank en camellones levantados es un sistema prometedor en regiones con periodo
corto de cultivo, por que intensifica el drenaje temprano del suelo durante la primavera y mejora la retención de agua del
suelo durante los períodos críticos de crecimiento y desarrollo del cultivo.
... Besides generating earlier yields, physiologically older seed-potatoes can also generate higher output (Perennec and Madec 1980, O'Brien et al. 1983, McKeown 1994. Increasing physiological age modifies growth response through a gradual loss of apical dominance (Iritani et al. 1983) and, in turn, can promote vigorous sprouting from meristems (Knowles and Botar 1991). Knowles and Botar (1991) reported that ageinduced changes in sprouting can also be used to reasonably predict both yield level and quality. ...
... Increasing physiological age modifies growth response through a gradual loss of apical dominance (Iritani et al. 1983) and, in turn, can promote vigorous sprouting from meristems (Knowles and Botar 1991). Knowles and Botar (1991) reported that ageinduced changes in sprouting can also be used to reasonably predict both yield level and quality. Early yields can also help reduce exposure of the potato crop to adverse weather, pests and other hazards that may limit yield and ⁄ or lower the quality of tubers (Horton 1987, Reust et al. 2001). ...
Enhancing physiological aging of seed-potatoes has the potential to substantially affect production, especially for short-season growing areas. This study analysed the effect of seed-tuber age and cultivar, jointly, to identify the combination for optimum early crop production, based on field experiments conducted at two locations in Nova Scotia, Canada. The potato cultivars Superior, AC-Novachip, Niska, and Yukon Gold were aged by exposing seeds stored at 4 °C to warming periods of 0, 242 (3 weeks), and 484 (6 weeks) day-degrees, prior to planting. Cultivar and age levels were completely randomized within each location and replicated four times. Harvest periods at 65, 80 and 95 days after planting (DAP) were analysed as an unbalanced split-plot factorial, with year as a random blocking factor, location as a whole plot treatment, and cultivar and age crossed as subplot treatments. Total yield and marketable yield from Yukon Gold improved with physiological age when harvested early at 65 and 80 DAP, while that from AC-Novachip improved when aged only 3 weeks. Niska was not affected by age. Overall, AC-Novachip was consistently better than the remaining cultivars, regardless of age. The best treatment combination that maximized marketable yield was Yukon Gold aged 6 weeks planted at a commercial farm and harvested 95 DAP. For early harvest (65 DAP), however, AC-Novachip aged 3 weeks and Yukon Gold aged 6 weeks generated the highest yields. Niska and Superior generated lower yield and higher culls.
... O'Brien et al. (1983), Allen and O'Brien (1986), calculations of physiological age based on degree-days of chitting are based on heat applied after sprouting begins. Knowles and Botar (1991 Botar ( ,1992 Furthermore, the optimum degree{ays for yield is considerably less than reported elsewhere, for example, 800-1000 degree-days (O'Brien et al. 1983) were recommended for the cultivars Home Guard and Maris Baird. Fewer degreedays of chitting were applied to the seed tubers in the present study than employed by other aurhors (Allen et al. 1979l' O'Brien et al. 1983; Allen and O'Brien 1986; Knowles and Botar 1992).It is possible that insufficient degree-days were given in the current study. ...
Potato cultivars Atlantic, Conestoga, Jemseg, Superior and Yukon Gold, grown for early markets and mid-season use in Ontario were evaluated for response to chitting in 1987 to 1989. Seed tubers were chitted at 8 °C commencing in January, for an average of 408, 284 or 172 degree-days (base 4 °C). Controls were stored at 4 °C. Plants emerged quicker from chitted seed and produced higher early yields than the controls. Approximately 260 degree-days of chitting was optimal for early yield of Jemseg and Superior. For maximum emergence, 318 degree-days was required for Jemseg. Commencing chitting before March did not increase yields for the other cultivars. Low degree-day requirements are likely the result of cold storage of seed prior to chitting, resulting in more rapid accumulation of degree-days and/or lower base temperatures for growth. Key words:Solarium tuberosum, cultivars, emergence, yield, physiological age
... There is a linear relationship between stem number and seed age. In the field, the older the seed, the more stems are produced (Knowles and Botar 1991;Knowles and Botar 1992). This stimulates competition between emerging shoots for light, water and nutrients and yields are often lower than physiologically young seed (Struik and Wiersema 1999;Fulton and Fulton 2000). ...
Poor quality seed is the major constraint limiting both the productivity of potato crops and the expansion of the potato industry in Vietnam. Despite numerous attempts to establish a certified seed system, the most practical solution is to import clean foundation seed of the desired variety and physiological age. With imports from Europe and North America proving to be immature and too expensive, Western Australia (WA) has emerged as a potential source of high quality seed. While seed imports from WA are unique in that the varieties imported have been selected by researchers in Vietnam as being suited to the agro-ecological environment in the Red River Delta (RRD), no assessment of the economic benefits to smallholder potato farmers from the use of WA potato seed has been undertaken. In 2006/08, the yield and profitability of three potato varieties Eben, KT3 and Atlantic in two locations were compared where the crops had been derived from new seed imported from WA (VN0), seed derived from crops cultivated in the RRD after one generation (VN1) and two generations (VN2). There was a significant difference in the yield produced between the three different seed sources but not between the locations. For all varieties, and in both years, the yield decreased with the number of multiplications in Vietnam. Furthermore, the marketable yield declined significantly from the first crop (VN0) to the third crop (VN2). The decline in yield and tuber quality with each successive generation was associated with an increase in PVY and PVX infection. Not unexpectedly, differences in yield and marketable yield between the seed generations had a significant impact on the gross income for each variety. VN0 seed of all varieties produced the highest gross income (VND 2.4 to 4.1 M/sao) compared to VN1 (VND 1.9 to 3.1 M/sao) which was significantly higher than VN2 (VND 1.4 to 2.4 M/sao). However, while high quality seed is more productive, it is also more expensive. As a result, significant differences were observed between the seed costs. VN0 seed was almost two times more expensive (VND 10,500 – 11,000 per kg) than VN1 and VN2 seed (VND 6,000 – 6,500 per kg). Despite the higher costs, VN0 seed provided the highest net incomes compared to VN1 which was significantly higher than VN2. Farmers who retained seed received a higher net income (VND 0.13 – 0.6 M/sao) than those who did not retain seed. Ways to improve the accessibility of affordable, high quality potato seed to farmers in the RRD are discussed.
A pot trial was conducted to study the effect of seed tuber physiological age on the leaf growth of two potato cultivars. The study was conducted in a controlled stress free environment in a glasshouse at University of Tasmania Horticultural Research Centre. Seed tubers of two cultivars (Atlantic and Russet Burbank) with different physiological ages were used. The trial was set up as a complete randomized block design with four replicates. Some leaf growth characters were observed including the leaf phenology and production. ANOVA on the observed parameters show a significant difference between the physiological ages of the seed tuber used in the leaf growth characters. Higher node or leaf appearance rate was observed in cv. Russet Burbank (39.5 °Cd per leaf) in the plants from older tubers compared to the younger seed tubers (51.2 °Cd per leaf). On the contrary, no significant differences were found for the leaf senescence rate. Seed tuber ages also affected the size of fully expanded leaves in cv. Russet Burbank but not in Atlantic. More branching was found in the plant established from physiologically older seed tubers.
