Rheological and Thermal Properties of Potato Starch

<正>Particle size, rheological and thermal properties of potato starch from Yunnan province of China was investigated. The particle size ranges from 0.429-102.3 μm determined by laser light-scatter. The major flow type of 6 w/v% potato starch was shear-thinning fluid even the shear rate up to 800·s-1, and the gel formed by 6 w/v% potato starch fell to weak gel for its little difference between G′ and G′′, high dependence on frequency and low value of G′(Pa). The hardness and cohesiveness of potato starch gel were 31.3 g and 131.9 g·s, respectively. The thermal properties of potato starch were also determined by DSC at the starch∶ water = 3∶ 1. The To, Tp, and △H of potato starch were 62.23℃, 67.31℃, and 2.22 J·g-1.     

Preservation of Disease-free Shoot Tips of Potato Germplasm through in vitro System

In vegetatively propagated crops,once system ati-cally infected w ith a viral disease,the pathogen canpassed from one generation to the next[1].Especially inpotato,contam ination by a pathogen can severely re-duce the total yield of the crop[2].Traditionally,potatovarieties have been and still m aintained in a fieldgene bank.M aintenance of potato germ plasm in thefield is a m ajor consum er of tim e,m anpower andspace aside from diseases and environm ental stresses.The m ajor disadvantage of …     

Selection of Suitable Parents in the Development of Potato Hybrids in Bangladesh

Potatoes(Solanum tuberosum L)are the thirdlargest food crop in Bangladesh following rice andwheat and make a major contribution to the total foodsupply of the country.Although in many westerncountries potato is the number one staple food,it is al-most entirely used as a vegetable in Bangladesh.Thepotato is a short duration crop that produces a largeamount of calories in a short period of time[1].Thepotato produces more protein and calories per unitarea per unit time than any other major food…     

Development and Evaluation of Codon-modified cry V Constructs in Cultivated Potato (Solanum tuberosum L. ) for Control of Potato Tuber Moth

A cryV gene,specifically toxic to Lepidoptera and Coleoptera,was incorporated into binary vectors with different promoters and the presence or absence of the β-glucuronidase(gus) reporter gene.These constructs were integrated into potato cv.Spunta by Agrobacterium tumefaciens-mediated transformation.Highest expression of cryV gene,determined by mRNA levels and insect mortality,was obtained using the CaMV 35S promoter without the gus gene configuration.Detached leaf and tuber bioassays showed a mortality rate of up to 83% and 100%,respectively,for potato tuber moth(Phthorimaea operculella Zeller) in the transgenic lines.Our results demonstrated that the presence of the gus gene negatively affects the expression level of the cryV gene.Bt expression was also facilitated by using the(ocs)3 mas super promoter,whereas the Bt expression regulated by the patatin promoter(tuber-specific) was too low to have any effect upon the mortality of potato tuber moth.These results represent significant improvement in the level of host plant resistance for the control of potato tuber moth via Bt transgenes.     

Somatic Mining for Phytonutrient Improvement of ‘Russet Burbank’ Potato

Screening of >800 somaclones of ‘Russet Burbank’, North America’s leading French fry cultivar, for improved yield and processing quality, led to the selection of 25 advanced lines. Three replicates of 3–5 tubers each from advanced lines were assessed after 5 months storage for antioxidant and polyphenol attributes; a subject receiving increased attention among plant breeders, nutritionists, and consumers. Phytonutrients affecting antioxidant components and total antioxidant capacity per serving (150 g fresh matter; one serving size) varied significantly among tubers of the 25 somaclones as well as between these somaclones and ‘Russet Burbank’ control plants (field tuber-derived and plantlet-derived). Several phenolics, including chlorogenic acid, caffeic acid derivatives, ferulic acid derivatives as well as the flavonoid rutin, ranged in concentration from 10- to 100-fold with some lines exceeding control tuber concentrations by >7-fold. Similarly, ascorbic acid ranged >3-fold (47.21 to 208.63 mg) on a per serving basis with some lines showing significantly greater concentrations than the control plantlet derived tubers (93.82 mg) by >2-fold. Antioxidant capacity, estimated using 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), ranged up to 5-fold for the advanced somaclones (2,121.34 to 11,163.07 μM trolox equivalent/serving). Less variation occurred with other antioxidant capacity tests (DPPH, Folin-Ciocalteu). Overall 17/25 lines had increased antioxidant components. HPLC assays were necessary to confirm lines with better phytonutrient profiles. Somaclonal selection offers clear benefits for phytonutrient improvement in potato and can follow selection for yield and processing attributes.     

Could the Supply of Boron and Zinc Improve Resistance of Potato to Early Blight?

The adequate supply of boron (B) and zinc (Zn) can improve the structural integrity and permeability of cell membranes, which is a defence mechanism against fungi infection. A greenhouse experiment was conducted to investigate the effect of the application of B and Zn on plant growth and the incidence and severity of potato early blight, a destructive foliar disease of potato crop caused by Alternaria grandis E.G. Simmons. Potato plants (Solanum tuberosum L. cv. Ágata) were grown in 11-l pots filled with sandy soil, unfertilized or fertilized with 5 mg kg^?1 B and 5 mg kg^?1 Zn (either alone or in combination). Potato plants were inoculated with isolates of Alternaria grandis at 40 days after planting. Early blight incidence and severity were evaluated visually 7 days after inoculation with A. grandis isolates. Disease incidence ranged from 16 to 41% infected leaves, and was significantly highest in the treatment with the application of B, followed by the control, and lowest with application of Zn and B + Zn. Early blight severity ranged from 2.5 to 25%, and was significantly higher in the unfertilized treatment than in those fertilized with Zn either alone or in combination with B. These findings suggest that Zn plays a critical role in potato tolerance to early blight and should be considered as a preventive measure in the disease management plan, since application of zinc reduced the incidence and severity of potato early blight. However, the physiological basis of this remains unknown.     

Potato growers 1961 yearbook acclaimed one of the nation’s finest

American Journal of Potato Research -     

Evaluation of “UFV Aeroponic System” to Produce Basic Potato Seed Minitubers

We evaluated misting nozzle types and the coating on the bucket’s inner wall on the yield of basic potato seed minitubers. Tubers of potato cv. Agata were sprouted in a non-acclimatized greenhouse from June to September 2013. Six treatments were evaluated, three types of misting nozzle (32 L/h with anti-drip, 32 L/h without anti-drip, and 9 L/h without anti-drip) and two types of bucket inner lining, with and without polyurethane, with four replications. Dry weight of roots, stems and leaves besides minituber number and tuber fresh weight were evaluated. The “UFV Aeroponic System” effectively produces minitubers and should be equipped with a fogger with an outflow of 32 L/h without anti-drip and no inner lining of the bucket for optimal yield.     

The Effect of Photoperiod on Tuberisation in Cultivated × Wild Potato Species Hybrids

Wild Solanum species offer a valuable source of genetic diversity for potato improvement. Most of these species are found in equatorial South and Central America and they do not tuberise under long-day photoperiods typical of those in the major potato production areas of North America, Europe and Asia. Crosses between two haploids of Solanum tuberosum Chilotanum Group as females and two wild Solanum species clones generated four hybrid families. The parents and progeny were subjected to two greenhouse trials to evaluate tuberisation at 20-, 14-, and 8-h photoperiods. Parents and offspring tuberised most readily at the 8-h photoperiod, and poorly or not at all at the 20-h photoperiod. Segregation for tuberisation in hybrids was apparent at the 14-h photoperiod and depended on the cultivated parent, but not the wild species parent. The data support previous studies and best fit a model in which tuber production under long photoperiods is controlled by two dominant genes in cultivated × wild species hybrids.     

Genetic Variance Estimates in Heterogeneous Potato Populations Propagated from True Potato Seed(TPS)

Twenty nine cross populations developed according to line x tester mating design along with their twelve parents raised from true potato seeds, were used to study variability and correlation for seven characters. The range of variation for all the characters were found to be wide and pronounced which indicated that characters were quantitative in nature and were under polygenic control. For all the characters, greater portion of the total δ^2p was mostly contributed by the δ^2g. Among the seven characters, tuber weight per plant showed the highest δ^2g, PCV, GCV, H2b, GA and expected GA%.On the other hand, dry matter contents (%) showed the lowest H^2b. Phenotypic and genotypic correlation coefficients of plant height with no. of tubers per plant and tuber weight per plant; no. of branches per plant with no. of tubers per plant and tuber weight per plant were found to be significant and positive.