Typical engineering design of potato micro-sprinkler irrigation in Northern Shanxi

The Loess Plateau in the northern part of Shanxi Province has uneven rainfall and large evaporation, so droughts often occur. The drought has restricted the development of the local planting industry and the economy. Micro sprinkler irrigation has the advantages of strong adaptability, saving water, saving labor and land, increasing production, and preventing salinization, which is very suitable for this area. This micro-sprinkler irrigation design is carried out in typical plots, based on potato plant characteristics, rainfall data over the years, combined with corresponding specifications and actual conditions. This article uses a refraction micro-sprinkler with a spray diameter of 2.4 m. In the water transmission and distribution network, underground pipelines share 1,860 m of main pipes and sub-main pipes; surface pipelines share 1,200 m of branch pipes and 90,000 m of capillary pipes. The design meets the verification indicators of all irrigation groups, conforms to local actual conditions.

Intensity of pest attack and yield of potato plant during offseason in Sajang Village, Sembalun District, West Lombok

Pests and diseases attacks are major limitation for white potato (Solanum tuberosum L.) production, and therefore intensive treatments are employed during the cultivation. There is an increasing constraint of the intensive pest control to sustainable potato production and environmental impacts; therefore it is crucial to select suitable cultivar, particularly for the rainy, off-season cultivation, at which production is scared. This research evaluated the intensity of pest attack and yield of two variety of white potato, designated as cv. Chitra and Atlantic, during rainy season. Experiment was conducted in Sajang Village, of Sembalun District, West Nusa Tenggara from March to June 2021. In the field, the plants were maintained according to common maintenance employed farmer in Sembalun, and data collected at two weekly basis. The results showed that symptom of pest attached was visible since the plants was 4 weeks old with no real different intensity between the two variety. A higher rate of pest intensity was recorded in Chitra variety compared to the Atlantic. However, the yield of the two varietie was not differing significantly. The results indicated that the two varieties could be cultivated during off-season and insects are not a major problem during offseason that limits potato plant growth and production in Sajang Village. Further study is needed to evaluate the potential cultivation of the two varieties whole year.

First Report of Pectobacterium punjabense causing potato soft rot and blackleg in Serbia

Soft rot and blackleg are common diseases affecting potato (Solanum tuberosum) production in Serbia. Pectinolytic plant pathogens belonging to the genera Pectobacterium cause soft rot and wilt diseases by plant cell wall degradation. These opportunistic phytopathogens lead to considerable economic losses in many potato-growing regions worldwide and are listed among top 10 plant pathogenic bacteria (Mansfield et al. 2012). Potato plants (cv. VR808) with symptoms of wilting, slow growth, stem blackening and tubers softening, were collected from a commercial potato field in Zobnatica (Serbia) in July 2019 and subjected to analysis. All symptoms occurred in the same field and the incidence of symptomatic plants was approximately 5%. Isolation was performed from 10 randomly chosen potato plant and tuber samples, expressing wilting and soft rot symptoms. Plant tissue was surface-disinfected and 1 cm length sections from the margins of lesions were macerated in sterile distilled water for 25 min and streaked on nutrient-agar medium. After 48 h of incubation at 26°C, predominant shiny, cream-colored, round colonies were obtained from all samples. Three representative isolates (MMZKVR1, MMZCVR2, and MMZKVR3) from independent samples were selected randomly and subjected to biochemical and pathogenicity tests. Isolates were gram-negative, nonfluorescent facultative anaerobes, exhibiting pectinolytic activity on potato tuber slices and hypersensitive response on tobacco leaves. They expressed catalase activity but did not express oxidase or acid phosphatase activity or produce indole. All strains grew at 37°C, in 5% NaCl, and reduced nitrate. Pathogenicity of the obtained isolates was tested on 3-week-old healthy potato plants (cv. VR808 and cv. Kiebitz) grown in commercial Baltic Tray Substrate (Hawita) in the greenhouse, as well as on potato tubers of the same varieties. Three potato plant stems per isolate were inoculated by the toothpick piercing method (Duarte et al. 2004) using bacterial suspension (approx. 1 × 108 CFU/ml). Inoculated plants were incubated under plastic bags in a greenhouse at 25 ± 2°C. Blackleg symptoms and stem wilting developed 48 hours after inoculation. No symptoms were observed on plants inoculated with sterile toothpicks dipped in sterile distilled water. The pathogen was re-isolated from symptomatic plants, fulfilling Koch's postulates and sequencing of 16S rDNA confirmed the originally isolated pathogen. Three potato tubers per isolate were inoculated by toothpicks dipped in bacterial suspension (approx. 1 × 108 CFU/ml). Inoculated tubers were placed in a sealed plastic container at 25 ± 2°C. Treatment with sterile distilled water was used as a negative control. Softening of the tissue around the inoculation point developed within 48 h from inoculation, and no symptoms developed on the control tubers. For molecular analyses, total DNA of the isolates was extracted using the DNeasy Plant Mini Kit (Qiagen). The isolates were not detected in diagnostic PCR assays using specific primers Br1F/L1R for the detection of P. brasiliense (Duarte et al. 2004) and primers EXPCCF/EXPCCR for P. catotovorum subsp. carotovorum (Kang et al. 2003). The 16S rDNA PCR amplification was performed using the universal PCR primer pair 27F/1492R (Fredriksson et al. 2013) and followed by Sanger sequencing (Macrogen Europe BV). The BLASTn analysis of sequences (GenBank Accession Numbers MZ048661, MZ048662, and MZ157274) revealed 100% query coverage and 100% identity to the sequences of Pectobacterium punjabense in NCBI (MT242589 and CP038498) isolated from potato in China and Pakistan (Sarfraz et al. 2018), respectively. All three obtained isolates were proposed to belong to Pectobacterium punjabense sp. nov. To further validate the identification, isolate MMZCVR2 of P. punjabense was selected for multilocus sequence analyses of 5 housekeeping genes (gyrA, recA, recN, rpoA and rpoS). The gyrA (MZ161817), recA (MZ161818), recN (MZ161819), rpoA (MZ161820) and rpoS (MZ161821) sequence analysis showed the highest nucleotide identity (99.44 to 100%) with P. punjabense strain SS95 (Sarfraz et al. 2018) previously deposited in NCBI GenBank database. To our knowledge, this is the first report of blackleg and soft rot caused by P. punjabense on potato in Serbia. Pectobacterium punjabense is a newly described species causing soft rot and blackleg disease in potato plants (Sarfraz et al. 2018). Its current geographic distribution is not well-described but important to know since soft rot bacteria are easily transported long distances in latently infected seed tubers and can cause significant economic losses in potato production worldwide.

Mapping Potato Plant Density Variation Using Aerial Imagery and Deep Learning Techniques for Precision Agriculture

In potato (Solanum tuberosum) production, the number of tubers harvested and their sizes are related to the plant population. Field maps of the spatial variation in plant density can therefore provide a decision support tool for spatially variable harvest timing to optimize tuber sizes by allowing densely populated management zones more tuber-bulking time. Computer vision has been proposed to enumerate plant numbers using images from unmanned aerial vehicles (UAV) but inaccurate predictions in images of merged canopies remains a challenge. Some research has been done on individual potato plant bounding box prediction but there is currently no information on the spatial structure of plant density that these models may reveal and its relationship with potato yield quality attributes. In this study, the Faster Region-based Convolutional Neural Network (FRCNN) framework was used to produce a plant detection model and estimate plant densities across a UAV orthomosaic. Using aerial images of 2 mm ground sampling distance (GSD) collected from potatoes at 40 days after planting, the FRCNN model was trained to an average precision (aP) of 0.78 on unseen testing data. The model was then used to generate predictions on quadrants imposed on orthorectified rasters captured at 14 and 18 days after emergence. After spatially interpolating the plant densities, the resultant surfaces were highly correlated to manually-determined plant density (R2 = 0.80). Further correlations were observed with tuber number (r = 0.54 at Butter Hill; r = 0.53 at Horse Foxhole), marketable tuber weight per plant (r = −0.57 at Buttery Hill; r = −0.56 at Horse Foxhole) and the normalized difference vegetation index (r = 0.61). These results show that accurate two-dimensional maps of plant density can be constructed from UAV imagery with high correlation to important yield components, despite the loss of accuracy of FRCNN models in partially merged canopies.

Problems of Managing Potato Plant Growth Under Micropropagation for Primary Seeds

This study shows the possibility of controlling the growth of potato microplants when adding the Murashige-Skoog (MS) nutrient medium chlorocholine chloride (CCC) to the composition at a concentration of 0.05-0.25 mg ⋅ L −1. Varietal specificity of the reaction of potato plants to the preparation was revealed. At optimal concentrations of CCC, plants with a stem length of 7-10 cm in 250 ml flasks were grown from single-node microcuttings for 1.5 months. Microplants were removed from the flasks using 20 cm scissors and unsterilized tweezers. The roots were shortened to 2-3 mm and the basal part of the stems was treated with a chalk-based paste containing 0.04% indolylbutyric acid (IBA). Plants were planted on 36 mm diameter Jiffy 7 peat pellets directly in the laboratory. The trays with the material were transferred to the greenhouse at the end of April at a temperature of 20-25 °C and placed in the conditions of the upper fine irrigation. After 3-4 days, mass root formation began in the plants, and another week later the seedlings were ready for use. By then the height of the plants was 10-15 cm, and the roots were clearly visible on the surface of the peat pellets. Planting these seedlings in a technological greenhouse to obtain minitubers was convenient and inexpensive. Keywords: potato, microcuttings, microtubers, minitubers, chlorocholine chloride, peat pellets