СОРТОИЗУЧЕНИЕ КАРТОФЕЛЯ В УСЛОВИЯХ ЮГО-ВОСТОКА КАЗАХСТАНА

Картофель в Казахстане по объемам производства, пищевой значимости и уровню потребления относится к приоритетным культурам. Площади картофеля в республике достигли 210 тыс.га, валовые сборы превысили 4 млн. тонн. Однако средние урожаи остаются все еще невысокими (18-19 т/га). В повышении продуктивности картофеля важное значение имеет подбор высокопродуктивных сортов. Агроклиматический потенциал реги-онов Казахстана благоприятствует возделыванию широкого разнообразия сортов картофеля. При этом необходимо использовать допущенные к использованию для конкретного региона сорта картофеля. В «Государственный реестр селекционных достижений, допущенных к использованию в Республики Казахстан» включено более 120 сортов картофеля, из них порядка 55%-зарубежной селекции. Для юго-востока Казахстана допущено к использованию около 30 зарубежных сортов. Однако большинство из них не обладают комплексом хозяйственно-полезных свойств. В этом аспекте необходимо создание сортов, отличающихся многими ценными признаками. Для картофелеводческих хозяйств наряду с продуктивностью большое значение имеют также качественные показатели и сохраняемость при хранении, устойчивость к вредоносным болезням и стрессовым факторам внешней среды. Поэтому весьма актуальны исследования по изучению адаптивных свойств и оценке хозяйственно-ценных признаков новых сортов картофеля, что обусловило проведение этой работы. В условиях предгорной зоны юго-востока Казахстана, на научном стационаре лаборатории селекции, семеноводства и биотехнологии картофеля Регионального филиала «Кайнар» ТОО «Казахский НИИ плодоовощеводства» проводилось сортоизучение картофеля. В 2018-2020 годы испытывалось 39 сортов картофеля зарубежной селекции и 14 сомаклонов, полученных методом клеточной селекции от зарубежных сортов Аладдин и Невский. Оценены процесс ягодообразования, жаростойкость, засухоустойчивость, устойчивость к опасным болезням, продуктивность, сохраняемость и поражаемость клубней при хранении. Из 39 зарубежных сортов картофеля выделено 7. Высокую устойчивость к засухе показали сорта Донцовский, Детскосельский. Высокую жаростойкость проявили сорта Буран, Астерикс, Славянка, Янтарь и Осень. По урожайности выделившиеся 7 сортов превысили отечественной сорт Эдем на 5,6-10,3 т/га. Дополнительные урожаи составили; сорт Буран - 10,3 т/га (46,61%), Славянка - 9,0 т/га (40,72%), Янтарный - 9,8 т/ га (44,34%), Дельфин - 10,0 т/га (45,25%), Донцовский - 5,6 т/га (25,34%), Коломбо - 7,4 т/га (33,48%), Осень - 8,1 т/га (36,65%). Высокую сохраняемость в 2 сезона хранения показали сорта Донцовский (Россия) - 89,9-91,4%, Коломбо (Голландия) - 89,3-91,8%. Пораженность клубней болезнями колебалась от 0,6% (Донцовский) до 10,3% (Russet Burbank). На основании результатов исследований для картофелеводческих хозяйств юго-востока Казахстана рекомендуются возделывать высокопродуктивные зарубежные сорта картофеля - Буран, Дельфин, Донцовский, Коломбо, Осень, Славянка и Янтарный.

Kinetics of Colour Development during Frying of Potato Pre-Treated with Pulsed Electric Fields and Blanching: Effect of Cultivar

The current research aimed to investigate the effect of pulsed electric fields (1 kV/cm; 50 and 150 kJ/kg) followed by blanching (3 min., 100 °C) on the colour development of potato slices during frying on a kinetic basis. Four potato cultivars ‘Crop77’, ‘Moonlight’, ‘Nadine’, and ‘Russet Burbank’ with different content of glucose and amino acids were used. Lightness (L* values from colorimeter measurement) was used as a parameter to assess the colour development during frying. The implementation of PEF and blanching as sequential pre-treatment prior to frying for all potato cultivars was found effective in improving their lightness in the fried products. PEF pre-treatment did not change the kinetics of L* reduction during frying (between 150 and 190 °C) which followed first-order reaction kinetics. The estimated reaction rate constant (k) and activation energy (Ea based on Arrhenius equation) for non-PEF and PEF-treated samples were cultivar dependent. The estimated Ea values during the frying of PEF-treated ‘Russet Burbank’ and ‘Crop77’ were significantly (p < 0.05) lower (up to 30%) than their non-PEF counterparts, indicating that the change in k value of L* became less temperature dependence during frying. This kinetic study is valuable to aid the optimisation of frying condition in deep-fried potato industries when PEF technology is implemented.

Simulación del área foliar en papa (Solanum tuberosum L.) con los modelos SUBSTOR-Potato y VEGA-Potato

El objetivo de esta investigación fue evaluar la simulación del área foliar en papa (Solanum tuberosum L.) con los modelos SUBSTOR-Potato y VEGA-Potato. Para cumplir este objetivo se utilizó el Sotfware DSSAT (Decision Support System for Agrotechnology Transfer) versión 4.5. El diseño fue pre experimental de nivel predictivo, se trabajó con dos variedades de papa Russet Burbank y Diacol Monserrat. Los resultados indicaron Con el nuevo modelo VEGA-Potato se encontró un IAF de 6.5 para la variedad Russet Burbank con un RECM 1.377 y para la biomasa 2207.6 mientras que para el modelo SUBSTOR-Potato se encontró un IAF de 5 con un RECM de 2.206 y para la biomasa 1617.3. Para la variedad Diacol Monserrat con el nuevo modelo VEGA-Potato se encontró un IAF de 7 con un RECM 1.073 y para la biomasa 1548.4 mientras que para el modelo SUBSTOR-Potato se encontró un IAF de 6 con un RECM de 2.462 y para la biomasa 1811.0. En conclusión, podemos decir que el nuevo modelo VEGA-Potato es más eficiente para la simulación del IAF y biomasa para las variedades de papa Russet Burbank y Diacol Monserrat.

Habituation to thaxtomin A increases resistance to common scab in ‘Russet Burbank’ potato

Common scab is a potato disease characterized by the formation of scab-like lesions on the surface of potato tubers. The actinobacterium Streptomyces scabiei is the main causal agent of common scab. During infection, this bacterium synthesizes the phytotoxin thaxtomin A which is essential for the production of disease symptoms. While thaxtomin A can activate an atypical programmed cell death in plant cell suspensions, it is possible to gradually habituate plant cells to thaxtomin A to provide resistance to lethal phytotoxin concentrations. Potato ‘Russet Burbank’ calli were habituated to thaxtomin A to regenerate the somaclone RB9 that produced tubers more resistant to common scab than those obtained from the original cultivar. Compared to the Russet Burbank cultivar, somaclone RB9 generated up to 22% more marketable tubers with an infected tuber area below the 5% threshold. Enhanced resistance was maintained over at least two years of cultivation in the field. However, average size of tubers was significantly reduced in somaclone RB9 compared to the parent cultivar. Small RB9 tubers had a thicker phellem than Russet Burbank tubers, which may contribute to improving resistance to common scab. These results show that thaxtomin A-habituation in potato is efficient to produce somaclones with increased and durable resistance to common scab.

Effect of steroidal glycoalkaloids on hatch and reproduction of the potato cyst nematode Globodera pallida

Steroidal glycoalkaloids (SGAs) are phytoanticipins found in solanaceous crops that act as the first line of chemical defense against pathogen attacks. Solanum sisymbriifolium, a trap crop for potato cyst nematodes, has been shown to effectively reduce populations of Globodera pallida. Solanum sisymbriifolium contains α- solamargine and other solasodine type glycoalkaloids that may contribute to plant defenses. The current study evaluated the influence of solanaceous SGAs on G. pallida hatch, development, and reproduction. Exposure to α- solamargine and α- solamarine reduced G. pallida hatch by 65 % and 87 % respectively. Exposure of G. pallida cysts with the glycoalkaloids α- solamargine and solasodine significantly reduced infection in susceptible potato Russet Burbank by 98 and 94 % compared to the control. Exposure of cysts to either solasodine or solamargine significantly reduced reproduction of G. pallida on Russet Burbank by 99 % compared to the control. The study demonstrated the deleterious effect of SGAs on G. pallida hatch, infection, and reproduction.

Identification and functional characterisation of late blight resistance polymorphic genes in Russet Burbank potato cultivar

In plants, the biosynthesis of the phenylpropanoid, flavonoid and fatty acid pathway monomers, polymers and conjugated metabolites play a vital role in disease resistance. These are generally deposited to reinforce cell walls to contain the pathogen to the site of infection. Identification of sequence variants in genes that biosynthesise these resistance metabolites can explain the mechanisms of disease resistance. The resistant and susceptible genotypes inoculated with Phytophthora infestans were RNA sequenced to identify the single nucleotide polymorphisms (SNPs) and insertion/deletion (InDel) variations. The SNPs/InDels were annotated and classified into different categories based on their effect on gene functions. In the selected 25 biosynthetic genes overlapping 39 transcripts, a total of 52 SNPs/InDels were identified in the protein-coding (CDS) regions. These were categorised as deleterious based on prediction of their effects on protein structure and function. The SNPs/InDels data obtained in this study can be used in genome editing to enhance late blight resistance in Russet Burbank and other potato cultivars.

Nitrogen rate and source effects on foliar sugar, glycoalkaloid, and amino acid composition of potato Russet Burbank

The foliar chemicals in potatoes (Solanum tuberosum L.) could affect the growth and development of agricultural pests, such as Colorado potato beetle, Leptinotarsa decemlineata (Say) and aphid, Macrosiphum euphorbiae. Thus, altering the chemical composition of potato leaves could potentially supplement integrated pest management (IPM). In this study, field experiments were conducted in Quebec, Canada, to investigate the effects of nitrogen (N) rates and sources on foliar sugar, glycoalkaloid, and amino acid concentrations and tuber yield of potato cv. Russet Burbank. Three N fertilizer sources of ammonium nitrate, ammonium sulfate, and polymer-coated urea were used at four N rates of 60, 120, 200, and 280 kg N ha-1 plus an unfertilized control in a randomized complete block design. The fourth leaves from the top of twenty randomly selected plants in each plot were collected at 54, 68, and 82 days after planting for sugar, glycoalkaloid, and amino acid analysis. Tubers were collected at harvest, and the total and marketable yields were measured. Results showed that N fertilization linearly decreased sugar concentrations and these reduced sugars were conveyed and stored in tubers as starch. Glycoalkaloid concentrations in leaves were influenced by N sources and rates. Both total and marketable yields quadratically varied with increasing N rates regardless of N sources, with average values of 36.4 and 28.3 Mg ha-1, respectively. Since N rate affected potato foliar chemical composition and tuber yield, N fertilization could be considered as a supplemental tool to the IPM strategy for potato pest control.