In the “State Food and Agriculture Policy’’ adopted by the Parliament of Mongolia Resolution No. 29 of 2003, increasing the nomenclature of food, technical, oil and fodder crops, in the soil and climate of the region of Mongolia and produce seeds of their localized varieties. Provides a specific part of domestic plant oil needs, and increases the range and production of strategic and import substitute foods. Rape is the main source of food and technical oils and fodder proteins, and lately it has grown considerably as an economically important to planting crop. To embed production is improving soil fertility, and increasing stabilization of grain yields in connection with Mongolian soil and climatic conditions is important for changing crop rotation structure. Planting of rape for 10-15% of grain production is an important issue of cultivation. Therefore our country it is urgent to develop proper cultivation of rape and technology of optimal protection against diseases, pests and weeds.

      A total weed species and density of the experimental fields was determined by methods of E.I. Liberschtaine and A. Tulikov,

      1. The soil samples taken 0-10 cm and 10-20 cm to determine weed seeds in contains soil by method of B.A. Dospekhov,
2. To deem technical result of herbicide,
3. To deem harvest by common method,
4. Production experiment field was 3 variant for soil cultivation per 1000 ha and 5 variant for planting time totaling 15 variants. Tornado 1l/ha, combination of Gallion 0.3l/ ha+ Miura 0.8l/ha herbicides were during growth stage, dosage of Tornado 1.5l/ha 1.8l/ha, Sukhovei 1.5l/ha, 1.8l/ ha herbicides to reduce seed moisture,
5. Plot experiment are planted mentioned above period, in growing season herbicide was did not used, there are 5 variant of timing difference, 1 plot size was 16m2 and total was 80m².

Climate features of the years studies

      Integrating of crop production activities and research results into key of agro climate indicators for the year, Tsagaannuur soum of Selenge province is region of central part of the cultivation area with the moisty chilly summer and cold winters, however the research years was conducted in favorable weather conditions. The average air temperature is 18-200 C in July, the coldest being around 20-220 C in January. The average annual precipitation is 300-350 mm and wind speed 1-3 m/sec. The ground frosts are observed in autumn in August-spring, in late May and early June. Compared MYA (many year avrage) with the 2017-2018 meteorological data for in the 2017 air temperature was 1.10°C higher, precipitation was 70mm higher, the number of days above 30°C was 21 days, the soil temperature was over 40°C day was 96 days, the number of precipitation days was 63 days, in 2018 average air temperature around the MYA, precipitation was 83.2 mm higher than MYA, number of days above 30 C was 95 days and 60 days with precipitation. The last spring ground frosts were May 28, 2017, May 22, 2018, and the first autumn ground frosts were August 28, 2017, and September 14, 2018 (climograph 1).

      Calculation study result of rape sown different time in cultivating mechanical, chemical fallow and direct straw field of Gatsuurt LLC of Tsagaannuur soum, Selenge province (Table 1).

Table 1

Table 1

      In 2017-2018, a total of 15 variants, 5 variants of the planting period and 3 variant of soil cultivation were to function in production experiment with a total area of 1000 ha. Before emerging the plant, herbicide of Tornado tested 1l/ha and combination of Galion 0.3l/ha+Miura 0.8l/ha herbicide applied in 2-6 leaves of rape during the growing season. Also, to reduce seed moisture before harvesting, Tornado herbicides were sprayed at 1.5l/ha, 1.8l/ha, Sukhovei herbicides at 1.5l/ha, and 1.8l/ha, respectively. During this time, the herbicides was not applied in plot experiment weed during the growing season to chose a convenient time.

Weed research in various soil cultivation variants.

      Different types of soil cultivation rape were planted on April 13, 20, 25, May 05, 10, 15. On April 13, the air temperature was 18C at day, -10C at night, the soil temperature was 40C, 70% minimum soil moisture content (MSMC) in 0-10 cm deep. The cultivated rape evenly sprouted around May 9, but in the ground freeze of this day, the emerged seeds were died. Therefore, it was suggested that optimal timing should be compared with MYA. The weed spread on the chemical and mechanical fallow areas planted between April 20 and May 5 was 10% or less (1 point), and on May 10 weed spread was 34% or below average (3 points) on chemical fallow, 25% or lower (2 points) in mechanical fallow, and 35% or more (4 points) in straw field, weed spread on mechanical fallow planted on May 15 was 15% or lower (2 points), 28% or average (3 points) in chemical fallow and 50% or more (4 points) in the straw field. Therefore spring summer annual and biennial weeds such as Proso millet ( Panicum millaceum L ), Marijiuna ( Cannabis ruderalis Janisch ), Leptopyrum fumarioides L , Sieversian wormwood ( Artemisia sieversiana Willd ) was spreading to dominate in the experinment field.

Research of weed seeds in soil

      The cultivated land contains hundreds of millions of germinative weed seeds and the main reason to determinant of the rate of field pollution is the fact that every year the seeds emerge and the soil weed seed resorces increasing. The weed seeds were sampled to a depth of 0-20 cm from the soil and identified. 9 weed species belongs to 6 genus and 5 family Amaranth (Amaranthaceae), Goosefoot (Chenopodiaceae), Bindweed (Convolvulaceae), Knotweed (Polygonaceae), Grasses (Poaceae) and Mallows (Malvaceae) weed seeds were detected in soil. Including: Common Mallow (Malva mohileviensis Downer), Goosefoot (Chenopodium album L), Red amaranth (Amaranthus retroflexuse L), Black bindweed (Polygonum convolvulus L), Proso millet (Panicum miliaceum L), Little lovegrass (Eragrostis minor Host) annual 6 weed species seeds were 66.7%, Pink champion (Silene repens Patr), curly dock (Rumex crispus L) and Field bindweed (Convolvulus arvensis L) perennial 3 species weed seeds 33.3% contained /table 2/

Table 2

Table 2

      Weed seed resource in the soil of rape field (million.pcs)

      Straw field contains 922.6 million /pcs 0-10cm layer of soil, 675.7 million /pcs 10-20cm layer of soil and it is higher than other variants.

Weed spread and density of experiment field.

      In 2017, 19 weed species belongs to 16 genus, 12 family were identified in the rape field of Tsaganuur soum in Selenge province, 10 species are 50% of annual, 2 species are 7.7% of biennial, 7 species are 42.3% of perennial weeds, in 2018, 16 weed species belongs to 15 genus, 15 family were recorded, 8 species are 53.3% of which were annual, 1 species are 6.6% of biennial, 6 species are 40% of perennial weeds, respectively. (1, 2- diagram).

      The weeds spread in the area of the experiment are classified by species: Proso millet ( Panicum millaceum L. ), Little lovegrass ( Eragrostis minor Host ), Red amaranth ( Amaranthus retroflexus L. ), Black bindweed ( Polygonum convolvulus L ), Goosefoot ( Chenopodium album L. ), slender Russian thistle ( S.collina Pall ), ( Leptopyrum Fumarioides L. ), Tackweed ( Tribulus terrestris L. ), Marijuana ( Cannabis ruderalis Janisch ), Common mallow ( Malva mohileviensis Downer ), Stephen’s stork’s bill ( Erodium stephanianum Willd. ), Siberian geranium ( Geranium sibiricum L. ), Sieversian wormwood ( Artemisia sieversiana Willd ), Quack grass ( Agropyron repens (L. ) Beauw), Meadow cranesbill ( Geranium pretense L ), Forked leaf ( Potentilla bifurca L. ), Field bindweed ( Convolvulus arvensis Ln. ) Common dandelion ( Taraxacum officinale Wigg.), British yellowhead ( Inula britannica L ) there were spreading 19 weed species.

Herbicide result on rape field

      When the weeds sprouted on the rapeseed field from seedling to germination, sprayed Tornado herbicide at a dose of 1l/ ha and it is eliminating the spring-summer weeds and emerging were evenly growing (Figure 1). Before sown emerge there were counted 96 weeds per 1m².

Figure 1: The after the use of Tornado herbicide before the rapeseed emerge.

      During the growing season in the rape field with 2-6 leaves, weeds total number counted of 116 per 1m2 the results were calculated by against broadleaf weeds spraying mixture of Gallion herbicide at 0.3l/ha and Miura herbicide at a dose of 0.8l/ ha, respectively (Figure 2).

Figure 2: Variants of timing difference before spraying of herbicide.

      Technical effectiveness of herbicides, % (rape field)

      The Tornado herbicide sprayed at the production field showed technical results of 91.6%, the combination of Gallion 0.3l/ha + Miura 0.8l/ha herbicide 95.7%. (Table 3, Figure 3).

Table 3

Table 3

Figure 3: Condition after spraying.

      In herbicide-free variants of the timing diffrent field, rape plants were predominantly grown before May 10, but after May 10 cultivated field the weed density was huge, to strangle and rape growth was limited, the pods and the seeds became moldy on their stems, which had a detrimental effect on the quality of the product. Therefore, taking into data the climate condition and soil moisture of the present year, it is necessary to correctly cultivate and carry out plant protection measures in expedient (Figure 4, Table 4).

Figure 4: Weeds to strangle around plantations leaves and stem.

Table 4

Table 4

      As can be seen from the table, on May 15, in the sown area, summer and autumn annual Green foxtail and Barnyard millet grew 75 pieces per 1m2, which is slowed down the growth of rape and affects nocuous the crop.

      Reducing rape seed moisture: In 65% of the total area before harvest the total field seed moisture content at 24-28%, 7-10 days after spraying Tornado herbicide at 1.5l/ha, 1.8l/ha, Sukhovei herbicide at 1.5l/ha and 1.8l/ha, the amount of moisture decreased to 7.9-8.3% (Figure 5, 6).

Figure 5: Seed moisture after 2 days after 5 days after 7 days Figure

Figure 6: Condition of reduced rape seed moisture.

      Indicator of rape yield: Shows the yield structure of timediffrent variants of straw field, mechanical fallow, and chemical fallow with different backgrounds (Table 4).

Table 5

Table 5

      As for soil cultivation, planted rapeseed on mechanical fallow from IV / 25 to May 11 with an average of 2 years yield was 16.1h / ha, which was best of all other variants. Therefore, mechanical fallow resulted in to set crop conditions on April 25 and 27, when the air temperature was 16 °C at night, -30 °C, the soil temperature was 5 °C and the MSMC was 75% at 0-10 cm depth (Figure 7).

Figure 7: The yield relation between on planting time in production field.

Biochemical indicators of crop:

      Biochemical indicators of planting diffrent timing rape. The biochemical of the rape was analyzed by the laboratory of the Gatsuurt LLC, the amount of moisture, butyric and protein was within the standard level.