Screening of 8 new strains of virus-free boll potato

1 materials and methods

1.1 A total of 9 new virus-free potato strains were tested, all of which were introduced from the potato breeding and virus-free center in Bijie Prefecture. The strain numbers are: B9904mur2, B9904mur1, B9901mur33, B9911mur1, B9911mur3, B9907mur4, B9910mur9, BP26, CK.

1.2 the test method was set on the contracted land of Chen Guangyi peasant household in Fengshan Village, Fengshan Township, Dafang County, with an elevation of 1682m, flat terrain and medium fertility. The former crop was ploughed and crushed soil before sowing, and the quality of land preparation met the requirements of the test. The single cropping experiment was arranged by single factor random block arrangement. 3 repeats, 27 plots, plot area 13.28m2, plot length 4m, width 3.32m, row spacing 0.66m, nest spacing 0.25m, 5 rows per plot, 16 nests per row, 80 nests in the whole plot, 60 000 nests per hectare.

The experiment was conducted on March 2, 2006, when the seeds were dug and sown with a whole potato block (25ml / 30g) in each litter. Farm manure 22500 kg and potato special compound fertilizer 375kg were applied as base fertilizer per hectare, but no topdressing was applied. Cover the soil and ridge after sowing. After finishing the seedlings, the soil was cultivated by the combination of ploughing and weeding on May 13.

2 results and analysis

2.1 yield table 1 showed that among the tested strains, the yields of B9904mur1, B9904mur2, B9901mur33 and B9910mur9 were higher than those of the control Mira, and the yield increase rates of the four strains were 25.85%, 17.42%, 13.70% and 10.64%, respectively. The yield of the four strains B9911, BP26 and B9907mur4 was lower than that of the control, and the yield reduction was 0.74%, 5.72%, 8.00% and 10.84%, respectively. The analysis of variance showed that the yield of B9904mur1 and B9904mur2 increased by 0.01 and 0.05, respectively, compared with the control. There was no significant difference in yield between the other strains and the control.

2.2 Seedling emergence dynamic Table 2 shows that all three repeats of the control Mira have all emerged, and the emergence rate is 100%, and the emergence rate is 100%. There is a full seedling in each of the two strains B9904 and B9910, and the rest of the experimental plots have different degrees of nesting phenomenon.

2.3 Table 3 of the growth period shows that the number of days from sowing to emergence of the control Mira and BP26 is the same, B9910 Mira 9 is 17 days earlier than the control Mira, and the other strains are 7 days later than the control Mira. In terms of the number of growth days from seedling emergence to maturity, the control Mira and BP26 were the same, B9910 Mel 9 was 11 days earlier than the control, B9904 Murray 2 and B9911 Mel 1 were the same, 12 days later than the control B9901 Mui 33 was 9 days later than the control, B9911 Mui 3 was the same as B9907 Mui 4, and 8 days later than the control, B9904mi 1 was 4 days later than the control.

2.4 main characters of underground part (Table 4)

2.4.1 the rate of large and medium potatoes. Among the tested lines, except for B9911 Mira, the percentage of large and medium potato of the other tested lines was higher than that of the control.

2.4.2 starch content. Among the tested lines, the starch content of BP26, B9907mur4, B9911mur3 and B9910mur9 was higher than that of the control Mila, while the other four lines were lower than that of the control Mila.

2.4.3 average number of tubers per plant. Among the tested lines, the number of tuber per plant of the tested lines was lower than that of the control, except that B9911mur3 was more than the control Mila.

2.4.4 average yield per plant. Among the tested lines, B9911mur3 was the same as the control Mira, while B99011Mui 1 and B9907 Mira 4 were lower than the control, while the other five tested lines were higher than the control Mira.

2.4.5 potato shape and skin smoothness. In terms of potato shape, the control Mira was long tube shape, B9904mur2, B9904mur1 and B9901mur333 lines were long oval, B9911-1, B9911mur3 and BP26 were round, and B9907mur4 and B9910mur9 were oblate. In terms of epidermis, B9904, B9907 and BP26 were hemp, the control Mira was rough, and the epidermis of the other tested strains were smooth.

2.4.6 skin color. Among the tested varieties (lines), except for B9904mur1, B9901Mel 33, B9911Mel 1 and B9910Mel 9, the skin colors of the other tested varieties (lines) were yellow. In terms of meat color, B9911mur3 was light yellow, B9901mur33, 139911mur1 and BP26 were milky white, and the rest of the tested varieties (lines) were yellow.

2.4.7 budding eyes. The bud eye number of all the other tested lines was less than that of the control Mila, and the bud eye depth of B9907 Mira 4 was the middle, and the bud eye depth of the other tested lines was shallow.

2.5.1 Plant shape and flower color. The plant shape of B9911mur3, B9907MUL4 and the control Mira were semi-erect, and the rest of the tested lines were erect. Except for 33 lines of B9904mur1, B9911mur1 and B9911murl, all the other varieties (lines) blossomed white.

2.5.2 plant height and stem diameter. The plant height (89.4cm) and stem diameter (0.6cm) of the control Mira were higher than those of the control Mira.

2.5.3 the number of main stems and branches. The number of main stem of BP26 and control Mira was 4.2.Among other tested varieties (lines), except for B9907Mur4, which was higher than that of control Mila, the number of main stem of other lines was less than that of control. The number of branches of all tested lines was more than that of the control Mila.

2.6 the disease only occurred leaf roll, late blight and powdery scab during the whole trial period (Table 6).

2.6.1 leaf curl. In the field, leaf roll disease occurred in B9904Mui 1, and the diseased plant rate was 2.5%. No leaf roll disease occurred in all the tested varieties (lines).

2.6.2 late blight. According to the survey on June 30th, only B9904mur1 and B9911Muel 1 had no diseased plants, and other varieties (lines) had varying degrees of late blight, among which the control Mira had the heaviest disease, with a disease grade of 3, with an incidence of 100%. The rest of the strains were grade 1, and the incidence rates of B9911mur3, B9907mur4, B9910RF9 and BBP26 were 80%, 80% and 50%, respectively. Lxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

2.6.3 Powder scab. Among the tested varieties (lines), no powdery scab occurred in B9904mur2, B9911mur1, B9907mur4, BF26 and the control Mira, but slight scab occurred in other lines.

3The characteristics and suggestions of the tested varieties.

3.1 the yield of B9904Mui 1 ranked first among the tested varieties (lines), and the yield was 420482kg/hm2 in the plot, which was significantly higher than that of the control Mila by 25.85%. The potato pieces were long and oval, the skin was yellowish, the flesh color was yellow, the bud eyes were few and light, the skin was smooth, the late blight occurred later, and the powder scab was mild. It is recommended to participate in the regional test and organize the production test.

3.2 the yield of B9904mur2 ranked second in the tested varieties (lines), and the equivalent yield in the plot was 392319kg/hm2, which was significantly higher than that of the control Mira, with a yield increase of 17.42%. Long oval potato pieces, yellow skin and yellow flesh, few bud eyes, shallow, smooth skin, resistance to powdery scab. It is recommended to participate in the regional test and organize the production test.

The yield of B9911mur3 ranked third among the tested varieties (lines), and the equivalent yield of 37989.5kg/hm2 in the plot was 13.70% higher than that of the control Mila, and the rate of large and medium potato was 91.28%, ranking first, 23.55% higher than that of the control. Potato-shaped long oval, yellowish skin, milky meat, smooth epidermis, few bud eyes, shallow. It is recommended that the identification should be continued.

3.4 the yield of B9910mur9 ranked fourth among the tested varieties (lines), and the equivalent yield of the plot was 36965.4kg/hm2, which was 10.64% higher than that of the control Mira. The potato is flat and round, yellowish skin, yellow meat, few bud eyes, shallow, smooth skin. It is recommended that the identification should be continued.

3.5 the yield of other varieties was lower than that of the control Mira. Because the experiment was conducted for only one year, and it was dry in the early stage of that year, there was rainy weather in the middle and last ten days of June, and the humidity in the field was high. In order to correctly evaluate the "three characters" of the new potato strain in Dafang County, it is suggested that the experiment should be continued in the following year.