Current issue

• 2023 Vol.13 No.8 Published:20 August 2023

  Study on the Construction of a Comprehensive Index Identification and Evaluation of Water Saving and Drought Resistance of Hybrid Rice Combinations KANG Haiqi, SUN Xiaowen, WANG Shimei, HE Fang, ZENG Yongxuan, QIN Rongmin, HAN Youxue, KANG Jiarong, ZENG Lin, ZHANG Hong 2023, 13 (8):  1-10.  DOI: 10.11923/j.issn.2095-4050.cjas2021-0223 Abstract + ( 187 )   HTML ( 11 )   PDF ( 1405KB )   ( 121 ) A gradient quantitative water control experiment was conducted with six hybrid rice combinations to simplify the technical system of the comprehensive evaluation of water conservation and drought resistance of hybrid rice combinations and their application in breeding. Observation records and traditional seed testing methods were employed to obtain yield data and other agronomic parameters. Based on the mapping and area algorithm of drought resistance index of each trait, five composite indexes of drought resistance involving multi gradient and multi traits were constructed by using five primary trait indexes, including yield and its component traits, sowing to heading days and harvest index. The five composite indexes were Y-PFK (the index of yield and its component), Y-HDD (the index of yield and the delayed effect of heading date), Y-HI (the index of yield and harvest index), CI1 (the comprehensive index 1) and CI2 (the comprehensive index 2). Each combination's five composite indexes were computed, and their mapping was analyzed. The results have shown that CI1, CI2, Y-PFK positively impacted the tested combinations' comprehensive evaluation of water conservation and drought resistance and were consistent with the actual field experience observation. The comprehensive evaluation of water conservation and drought resistance of the six hybrid rice combinations were as follows: ‘Hanliangyou 8' > (‘Yayou Hanhe' > ‘Hanyou 737') > (‘Hanyou 73' > ‘Quanyou 116' > ‘Quan 9you 86'). The research findings demonstrate that the multi-gradient and multi-traits composite indexes of drought resistance, Y-PFK, CI1 and CI2, are appropriate for comprehensively evaluating rice's water conservation and drought resistance. These are simplified indicators for the comprehensive assessment and sequencing of water conservation and drought resistance of hybrid rice combinations by only using conventional seed testing data. These composite indexes can be applied to rice breeding for water conservation and drought resistance.

  Effects of Different Sowing Dates on Dry Matter Accumulation and Transport and Yield of Wheat ‘Taikemai 31' CUI Zhaoyun, ZOU Junli, XU Yi, YIN Xundong, LV Guangde 2023, 13 (8):  11-17.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0128 Abstract + ( 185 )   HTML ( 7 )   PDF ( 1476KB )   ( 174 ) To investigate the effects of different sowing dates on dry matter accumulation and transport, leaf area index (LAI), grain filling rate and yield structure of a new wheat variety ‘Taikemai 31', experiments with different sowing dates were conducted in the wheat growing season from 2019 to 2021. The dry matter accumulation, leaf area index (LAI), grain filling rate and yield structure of ‘Taikemai 31' at different growth stages were measured under different sowing dates (September 30, October10, October 20 and October 30), which were denoted as SD1, SD2, SD3 and SD4. The results showed that, under SD2 treatment, ‘Taikemai 31' had the highest dry matter accumulation in the whole growth period, and the highest dry matter accumulation from jointing to flowering and from flowering to maturity; the contribution rate of dry matter accumulation after anthesis to grains was SD2>SD1>SD3>SD4. In the overwintering stage and returning to green stage, the effect of sowing date on leaf area index of ‘Taikemai 31' was SD1>SD2>SD3>SD4, but after returning to green stage, the effect on leaf area index was SD2>SD3>SD1>SD4. The grain filling rate of the variety increased rapidly during the 15th-25th day at grain filling stage, and reached the highest on the 25th day. The grain filling rate increased slowly during the 25th-30th day, and the grain filling growth under SD4 treatment was significantly higher than that under other sowing dates. The yield of ‘Taikemai 31' was the highest under SD2 treatment, and the correlation analysis showed that the highest spike number was conducive to the highest yield under SD2.

  Effects of Maize and Soybean Intercropping on Agronomic, Quality and Yield Traits of Soybean ZHAO Xiaoguang, ZHAO Xingzhong, LIU Haomeng, XIAO Jinping, ZHANG Pu, ZHANG Yalei, WANG Liping 2023, 13 (8):  18-24.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0022 Abstract + ( 224 )   HTML ( 10 )   PDF ( 1189KB )   ( 169 ) In order to expound the changing rules of agronomic traits, quality traits and yield traits of soybean varieties under maize and soybean intercropping mode, 7 soybean varieties and maize variety 'Shandan 650' were selected for intercropping, and the differences of various traits of soybean varieties under the intercropping and the monocropping modes were analyzed. The results showed that the plant height, pod height and nodes on main stem of intercropping soybeans were higher than that of monocropping soybeans, but the pod number per plant and pod density of intercropping soybeans were lower than that of monocropping soybeans, and the growth period of intercropping soybeans were longer than that of monocropping soybeans; the crude fat and protein of intercropping soybeans were higher than that of monocropping soybeans, the content of saturated fatty acid of intercropping soybeans were lower than that of monocropping soybeans, but the content of linoleic acid and linolenic acid of intercropping soybeans were higher than that of monocropping soybeans; the grain weight per plant, number of grains per plant and number of grains per pod of intercropping soybeans were lower than that of monocropping soybeans. The changing rules of 100-grain weight were not consistent among different varieties. The average yield of 7 soybean varieties under intercropping mode was 49.88% lower than that under monocropping mode. Through the analysis of various traits, it provided strong support for us to select suitable soybean varieties in different regions for maize and soybean compound planting.

  Study on the Water Surplus and Deficiency of Potato in the Central and Southern Ningxia MA Liwen, LIU Jing, XU Qing, ZHENG Fang, ZHANG Xueyi 2023, 13 (8):  25-31.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0093 Abstract + ( 133 )   HTML ( 7 )   PDF ( 1327KB )   ( 98 ) Understanding the potato water requirement, water surplus and deficit in the central and southern areas of Ningxia can provide support for rational arrangement of the supplementary irrigation schedule and improvement of the water use efficiency. Using FAO PM 56 method and field water balance equation, the changes of water requirement, consumption and water surplus and deficit of potato were analyzed by refining Kc coefficient. The results showed that the water requirement of potato during the whole growth period was 465.1-677.3 mm, which was significantly positive and negative correlation with temperature and precipitation, respectively. The water requirement was more in high temperature years, less in low temperature years, less in rainy years, and more in less rainy years. The water deficit at seedling and tuber expansion stage was positive, and most of it was negative from June to early August, and there were 7-12 ten days water deficit exceeding 10 mm/ten days. The period of water shortage was gradually extended from south to north, and the amount of water shortage was gradually increasing. The accumulated water deficit in the central arid zone from June to August was more than 300 mm. For this reason, measures can be applied such as drought-tolerant varieties, low-water consumption preceding crop, fallow rotation, plastic film mulching, ridge and furrow cultivation, water-saving supplementary irrigation during water deficit period to support the sustainable development of potato planting.

  Distribution Characteristics of Soil pH in Cultivated Land in Qinling-Bashan Area and Its Influencing Factors GAO Peng, YANG Xiaomin, LI Danni, YU Zhengjun, YAO Yuan, SI Hua 2023, 13 (8):  32-36.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0140 Abstract + ( 129 )   HTML ( 3 )   PDF ( 1593KB )   ( 87 ) To explore the distribution characteristics of soil pH of cultivated land in Qinling-Bashan area, this study took Hanzhong City in Shaanxi Province as the research area, and analyzed the distribution law of soil pH in cultivated layer and its influencing factors by geostatistical and GIS methods. The results showed that the regional soil pH was between 4.15 to 8.41, with an average value of 6.50, and the overall soil was weakly acidic to neutral. The spatial distribution of soil pH showed the characteristics of low in the middle and high in the east and west. The distribution of soil pH in this area was affected by both structural factors and human factors. The results of geostatistical analysis showed that the optimal theoretical model of the soil pH variation was the exponential model, and the nugget effect value was 0.366, which indicated that the spatial heterogeneity of regional variables was the result of the joint action of random factors and structural factors, among which the soil type, farming system, soil parent material and altitude were the main influencing factors. This study could provide a theoretical basis for rational utilization of cultivated land and sustainable agricultural development.

  Effects of Continuous Straw Returning on Rice Yield and Nitrogen Utilization MENG Ruoxi, WANG Xiaoli, DUAN Jianjun, XU Bin, YANG Hongwei, MEI Tingting 2023, 13 (8):  37-45.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0113 Abstract + ( 146 )   HTML ( 5 )   PDF ( 1453KB )   ( 148 ) To clarify the impact of straw returning ratio on rice yield and nitrogen utilization, a field plot positioning experiment was conducted in Tangtou Town, Sinan County of Guizhou Province during the rice growing season from 2019 to 2021. Six treatments were set up in the experiment: CK was no fertilizer, S0 was conventional fertilizer, S1 was conventional fertilizer + straw returning 5 t/hm2, S2 was conventional fertilizer + straw returning 10 t/hm2, S3 was conventional fertilizer + straw returning 15 t/hm2, and S4 was conventional fertilizer + straw returning 20 t/hm2. The results showed that from 2019 to 2021, the yield of S3 treatment was the highest, increased by 20.16%, 8.66% and 14.40% respectively compared with that of S0 treatment, and the yield increase in 2019 was the highest. The reason for the yield difference was that straw returning to field improved the number of effective panicles, the number of grains per panicle, 1000-grain weight and seed setting rate of rice, and then significantly increase the yield. The fitting analysis of straw returning and rice grain yield showed that the highest grain yield was achieved by straw returning amount of 15.43 t/hm2. Straw returning could improve the nitrogen partial factor productivity and nitrogen harvest index between years. In 2019, the nitrogen partial factor productivity of S3 treatment was the highest, while the nitrogen harvest index of S4 treatment was the highest, which were 42.81% and 24.30% higher than those of S0 respectively. In 2020, the nitrogen partial factor productivity and nitrogen harvest index of S3 treatment were the highest, with an increase of 55.98% and 22.61% over those of S0 treatment respectively; and in 2021, the nitrogen partial factor productivity and nitrogen harvest index of S3 treatment were also the highest, with an increase of 21.75% and 15.88% over those of S0 treatment, respectively. Straw returning increased the physiological utilization rate of nitrogen between years, and S3 treatment had the best effect, with an increase of 72.97%, 76.14% and 52.98% respectively compared with that of S0 treatment from 2019 to 2021. Moreover, year and straw returning treatment significantly improved the physiological utilization rate of nitrogen and agricultural efficiency of nitrogen. Therefore, considering rice yield, straw returning fitting results and nitrogen utilization rate, S3 treatment is more suitable for straw returning.

  Impacts of Various Tree Species on Spatial Heterogeneity of Soil Dissolved Organic Carbon in Forest Ecosystems KONG Lingqian, LIU Xianbin, LI Yun 2023, 13 (8):  46-55.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0112 Abstract + ( 155 )   HTML ( 3 )   PDF ( 1274KB )   ( 84 ) To investigate the contents of soil dissolved organic carbon and soil organic carbon in the rhizosphere of several tree species in different sampling places in a forest ecosystem, the factors affecting the spatial heterogeneity of soil dissolved organic carbon and soil organic carbon in forest ecosystem were analyzed. This project was carried out in the subtropical montane moist evergreen broad-leaved primary forest ecosystem in Ailao Mountains of Yunnan Province. Seven dominant tree species in the primary soil area of forest ecosystem with high altitude in three sampling watersheds were selected as the research objects to investigate the contents of soil dissolved organic carbon and soil organic carbon in the 0-10 cm topsoil. The results showed that the contents of soil dissolved organic carbon and soil organic carbon in the rhizosphere of 5 tree species, including Lithocarpus hancei (Bentham) Rehd., Castanopsis rufescens (Hook. f. et Thoms.) Huang et Y. T. Chang., Lithocarpus xylocarpus (Kurz) Markg., Symplocos ramosissima Wall. ex G. Don and Schima noronhae Reinw. ex Bl. Bijdr, were significantly higher than those in the rhizosphere of the other 2 shrub species, namely, Camellia forrestii (Diels) Coh. St. and Vaccinium duclouxii (Levl.) Hand.-Mazz.. Among the 5 tree species, the contents of soil dissolved organic carbon and soil organic carbon in the rhizosphere of L. hancei and S. noronhae were significantly higher than those of the other 3 species, indicating that different tree species could apparently affect the spatial heterogeneity of soil dissolved organic carbon and soil organic carbon. The contents of soil dissolved organic carbon and soil organic carbon as well as the proportion of soil dissolved organic carbon in soil organic carbon in the rhizosphere of the 7 sampling tree species respectively reached the maximum value in the Laojunshanshen watershed, and decreased to the corresponding lowest value in the Sankeshu watershed, indicating that the environmental factors in different sampling watersheds could also obviously affect the contents of soil dissolved organic carbon and soil organic carbon as well as the ratio between them. The research results of this project fully proved the complexity of the spatial distribution of soil dissolved organic carbon and soil organic carbon in forest ecosystems and the diversity of environmental controlling factors, and could provide new scopes for the research on soil organic carbon composition and carbon storage in various types of forest ecosystems in the world.

  Agricultural Mulching Film in Shiyan: Application Status and Pollution Control Countermeasures WANG Xiaoxi, SONG Yingran, HUANG Xiaoshan, LI Tao, TANG Ran, HE Jian, LI Hui, LIN Shan 2023, 13 (8):  56-62.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0092 Abstract + ( 142 )   HTML ( 9 )   PDF ( 1125KB )   ( 99 ) At present, the application of plastic mulching film in agricultural production, such as the using amount, the mulching area and the mulching crop species, has increased year by year in Shiyan, causing a large amount of mulching film residues and serious pollution to agricultural environment. Based on statistical data and the actual situation, it can be seen that the prevention and control of agricultural mulching film residue pollution and the application of new type of mulching film have become an urgent task, which is of great significance to environmental protection and agricultural development in Shiyan. The study analyzed current situation of agricultural mulching film application and problems in film recycling in Shiyan, and put forward corresponding countermeasures and suggestions, aiming to provide reference for the prevention and control of mulching film pollution in the area.

  Olfactory Behavioral Responses of Pachyrhinus yasumatsui to Volatiles of Different Varieties of Jujube Trees ZHANG Peng, YANG Jie, YAN Xiongfei, MA Xinxing, ZHANG Quan, SHI Huifang 2023, 13 (8):  63-68.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0037 Abstract + ( 118 )   HTML ( 2 )   PDF ( 1206KB )   ( 85 ) This study clarifies the preference of newly emerged Pachyrhinus yasumatsui adults for different jujube cultivars, and provides basic data for elucidating the chemical communication mechanism of host orientation and screening resistant varieties of jujube trees. In this experiment, using jujube buds, branches, and leaves of five jujube varieties as plant materials, the olfactory behavioral responses of P. yasumatsui adults to the volatiles of the above plant materials were measured by a Y-tube olfactometer and a disc trap olfactometer. The results of Y-tube olfactory test showed that with the clean air as control, the selection rate of five jujube bud volatiles by P. yasumatsui adults was 69.0%-79.2%. The volatiles from five jujube buds had significant attraction to P. yasumatsui adults (P<0.05), while volatiles from ‘Muzao' buds had extremely significant attraction to adults (P<0.01). The number of odor arms of the five jujube leaves selected by adults was not significantly different from that of the air control arm (P>0.05). The selection rate of volatiles emanating from five jujube branches by P. yasumatsui adults was 66.7%-75.0%, and volatiles from jujube branches of ‘Muzao', ‘Goutouzao', ‘Suanzao' and ‘Junzao' had significant attraction to adults (P<0.05). The results of disk trap olfactory test showed that P. yasumatsui adults had obvious selectivity for volatiles from buds and branches of different jujube cultivars. The selection rate of P. yasumatsui adult for buds and branches of ‘Muzao' was significantly higher than that of air control (P<0.05). The selection rate of female adult to the buds and branches of ‘Zanhuangzao' and ‘Junzao' was not significantly different from that of air control. In conclusion, the volatiles from buds and branches of ‘Muzao' have the strongest attraction to P. yasumatsui. ‘Muzao' has the weakest resistance to P. yasumatsui, while ‘Zanhuangzao' and ‘Junzao' have stronger resistance to them.

  Breeding of a New Brassica alboglabra Variety ‘Qiubao kale' LI Tingyao, LI Guihua, WU Zengxiang, CHEN Hancai, SHEN Zhuo, ZHOU Xuan, YANG Yi, ZHANG Yan 2023, 13 (8):  69-73.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0119 Abstract + ( 126 )   HTML ( 2 )   PDF ( 1217KB )   ( 73 ) In order to enrich the genetic resources of Chinese kale and improve the level of kale hybrid breeding, ‘Qiubao kale', a new hybrid kale variety prepared by using cytoplasmic male sterile line, was bred. The variety has the characteristics of medium maturity, excellent quality and good marketability. The leaves of ‘Qiubao kale' are nearly round, with a leaf length of 16.0 cm and a leaf width of 15.7 cm. The stem is 19.8 cm in length and 1.8-2.0 cm in thickness, and the mass of a single stem is 100-120 g. It takes 55-60 days from sowing to first harvest. The average yield of the regional test is 9593.9 kg/hm2, an average increase of 11.0% compared with that of the control variety ‘Shunbao kale'. ‘Qiubao kale' has strong waterlogging tolerance, disease resistance and wide adaptability, and its suitable sowing period in Guangzhou is from September to late November.

  Effects of Quantitative Pruning and Spraying Apple Mask on Economic Benefit of Apple Orchard BAI Dujuan, NIU Yuhua, BAI Gangshuan 2023, 13 (8):  74-80.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0095 Abstract + ( 124 )   HTML ( 3 )   PDF ( 1286KB )   ( 70 ) To reduce labor cost and improve economic benefit of apple orchard, taking conventional pruning apple orchard as the control, the effects of quantitative pruning on labor cost of thinning flower and fruit, fruit quality and economic benefit of orchard were monitored in Weibei dry plateau. Taking fruit bagging (paper bag) as the control, the effects of spraying apple mask (humic acid type apple bag-free liquid film agent) instead of fruit bagging on labor cost, apple quality and economic benefit of orchard were monitored in the hilly-gully region of northern Shaanxi. The results showed that quantitative pruning paid 4500 yuan/hm2 labor cost more than conventional pruning in winter, but paid 11250 yuan/hm2 less when thinning flower, and 2250 yuan/hm2 less when thinning fruit. Quantitative pruning increased mean fruit weight and fruit quality, the fruit output value increased by 13.73%, and economic benefit of orchard was 34860 yuan/hm2 higher than that of conventional pruning orchard. Compared with fruit bagging and debagging, spraying apple mask reduced labor cost by 22850 yuan/hm2 and reduced material consumption by 8250 yuan/hm2, improved the appearance commodity value and storage and transportation performance of apple, and the fruit output value increased by 50.01%, the economic benefit of orchard was 192900 yuan/hm2 higher than that of fruit bagging orchard. In conclusion, quantitative pruning and spraying apple mask can reduce labor cost and improve economic benefit of apple orchard, which should be actively carried out in the process of apple orchard management.

  The Characteristics of Chilling Requirement and Limit Temperature of Jujube in the Middle Section of Taihang Mountains in Hebei Province LIANG Chunwang, ZHANG Kejia, YANG Lina, JIA Qiulan, HAN Xiangyang, WU Yunlong 2023, 13 (8):  81-88.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0052 Abstract + ( 124 )   HTML ( 2 )   PDF ( 2562KB )   ( 66 ) Based on the daily temperature data from 1991-2021 of the 11 counties in the middle section of the Taihang Mountains, using the trend analysis and Pearson coefficient, the limit temperature of 7.2℃ for dates entering dormancy and the chilling requirement during dormancy of the jujube in the middle section of the Taihang Mountains were analyzed. The results showed that the average date of the initial day when temperature steadily dropped to 7.2℃ in the middle part of Taihang Mountains was November 10th, the earliest date was November 9th, the latest date was November 11th, and the changes were insignificant. The average date of the initial day when temperature steadily rose to 7.2℃ was March 18th, the earliest date was March 15th and the latest date was March 20th, which was a significant change in trend of 4.2 d per 10 years. The average days of the temperature steadily dropped to 7.2℃ was 128.8 d, the minimum number of days was 125.1 d, and the maximum number of days was 132.3 d. The change in trend was 5.1 d/10 a, which was a significant change. For the temperature dropped steadily to 7.2℃ throughout the day, Quyang and Fuping were the earliest area; among the initial days when the temperature rosed steadily to 7.2℃, Luquan and Zanhuang were the earliest area. The consecutive days which the temperature fell steadily to 7.2℃ were the least in Luquan, western Yuansi and Zanhuang. The change in trend of consecutive days in Quyang decreases by 4.0d per 10a; there was a low value area of the chilling requirement in Luquan, Zanhuang and Lincheng when the temperature steadily dropped to 7.2℃. There was a low value area of the chilling requirement in Quyang and the north of Fuping, when the temperature steadily dropped between 0℃ and 7.2℃. This study can provide a clearer understanding about chilling requirement of the jujube in the middle part of the Taihang Mountains in Hebei Province, which can provide scientific guidance for planting different varieties of jujube trees in this region.

  Application of Neural Networks Based on Gray Relation in Forecasting the Initial Flowering Date of Nanguo Pear ZHAN Shenye, LV Xiao, JIN Dandan, KANG Xiaoyu, HAN Yanfeng, HAN Guojing, XU Qingzhe, TIAN Lu 2023, 13 (8):  89-93.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0009 Abstract + ( 123 )   HTML ( 1 )   PDF ( 1289KB )   ( 75 ) To explore a more accurate and effective method to predict the initial flowering date of Nanguo pear, grey relation analysis was used to determine the winter meteorological factors associated with the initial flowering date, which could be used as BP (Black Propagation) neural network and RBF (Radial Basis Function). The root mean square error (RMSE) and relative error (RE) were used to evaluate the prediction effect of the model. Meanwhile, the stepwise regression equation was established by comparing the winter meteorological factors significantly related to the initial flowering date of Nanguo pear and the prediction results after back substitution. The following are the results. (1) The meteorological factors with greater grey relation with the initial flowering date of Nanguo pear were the daily average temperature, maximum temperature, minimum temperature and relative humidity in winter, and the correlation degree was above 0.6. Therefore, these four factors were used as the input layer of BP and RBF neural network models to predict the initial flowering date of Nanguo pear. (2) The meteorological factors significantly correlated with the onset of flowering were daily mean temperature, daily mean ground temperature of 5 cm, daily minimum temperature and daily maximum temperature, and the correlation coefficients were -0.646, -0.628, -0.638 and -0.663, respectively. All the established regression models passed the significance test and had statistical significance. (3) The accuracy of model fitting established by BP and RBF was generally close. (4) The errors of BP neural network and RBF neural network prediction results based on grey relation were 1 day and 2.25 days respectively, and the flowering date predicted by BP neural network was closer to the actual flowering date. (5) RMSE, RE and R2 of BP neural network model based on grey relation were 1, 6.34% and 0.7, respectively, and for RBF neural network model, RMSE was 2.25, RE was 13.13%, and R2 was 0.568. In conclusion, BP neural network model established by grey relation analysis method was more accurate than RBF model in predicting the initial flowering date of Nanguo pear.

  Study on the Variation of Frost Characteristics and the Intensity of Disaster-causing Risk in Northwestern Liaoning WANG Yi, WANG Ding 2023, 13 (8):  94-100.  DOI: 10.11923/j.issn.2095-4050.cjas2022-0104 Abstract + ( 128 )   HTML ( 3 )   PDF ( 1341KB )   ( 98 ) Frost events are among the most severe meteorological extreme events associated with agriculture. The study on frost variation trend and intensity is conducive to improving people's understanding of frost and has certain reference value for agricultural structure adjustment. Using meteorological data and phenology data of crop seedling stage and fruit tree flowering and ripening stage from 1951 to 2020 in Chaoyang and Fuxin of Liaoning Province, the authors applied climate diagnostic analysis methods to analyze frost occurrence time and frequency, and study the intensity of disaster-causing risk of frost in northwestern Liaoning. The results showed that the disaster intensity of spring frost after May 1 was >80%, the risk intensity of the last frost was 41.6% on average, and the probability of severe disaster (70%<ST≤100%) was 20.0%. Because the last frost date was earlier by -0.438 d/10 a, the spring frost disaster risk intensity linearly decreased by 9.4 percentage points, while the spring frost disaster risk intensity decreased on average by 5.2 percentage points from 2001 to 2020. Before September 15, the disaster intensity of autumn frost was greater than 80%, the average risk intensity of the first frost was 27.7%, and the probability of severe disaster (70%<ST≤100%) was 5.7%. Because the first frost date was delayed by 1.734 d/10 a, the disaster risk intensity decreased linearly by 34.0 percentage points, while the frost disaster risk intensity in autumn of 2001 to 2020 decreased by an average of 24.9 percentage points. The annual frost disaster risk intensity decreased linearly by 25.6 percentage points; from 2001 to 2020, it decreased by 17.1 percentage points. The results indicate that under the influence of climate warming, the annual frost disaster risk intensity in northwestern Liaoning has been generally weakened, while the advance trend of the last frost date is unstable, and it is necessary to be cautious in adjusting the planting date of crops. From 1991 to 2020, the first frost disaster risk intensity decreased obviously, so there is room for development and utilization of heat resources in autumn.