[Objective]Calcium is involved in a variety of physiological metabolic processes in plants and regulates the growth and development of plants.Camptotheca acuminata has poor drought resistance.This study aimed to explore the potential of exogenous calcium in improving the drought resistance of Camptotheca acuminata.[Method]The effects of different concentrations of CaCl2 on the growth and physiology of seedlings under PEG treatment were analyzed by PEG 4000 simulated drought stress.[Result]The results showed that compared with the control(0%PEG),10%PEG caused obvious stress damage to seedlings,decreased survival rate and biomass,increased relative water deficit(RWD)of leaves,decreased net photosynthetic rate(Pn),water use efficiency(WUE),intercellular carbon dioxide concentration(Ci)and chlorophyll content,increased transpiration rate(Tr),stomatal conductance(Gs)and malondialdehyde(MDA)content,and decreased SOD and POD activities.Under the action of 2-6 mg·L-1 CaCl2,the seedlings of the control treatment showed the effect of low promotion and high inhibition.When the concentration of CaCl2 was 6 mg·L-1,the growth physiology of the seedlings was significantly inhibited,while the growth physiology of the seedlings treated with 10%PEG was significantly improved.The seedling survival rate,biomass increment,leaf RWD,Pn,Tr,WUE,Gs,Ci,chlorophyll content,SOD activity,POD activity,CAT activity and MDA content were used as evaluation indexes,and comprehensive evaluation was carried out by principal component analysis.The physiological performance of seedling growth under 4 treatments of 10%PEG +0-6 mg·L-1 CaCl2 was ranked as follows:10%PEG+4 mg·L-1 CaCl2＞10%PEG+6 mg·L-1 CaCl2＞10%PEG+2 mg·L-1 CaCl2＞10%PEG+0 mg·L-1 CaCl2.[Conclusion]The results indicated that exogenous CaCl2 could significantly improve the drought resistance of Camptotheca acuminata seedlings.Under the treatment of 10%PEG 4000,the effect of 4 mg·L-1 CaCl2 was the best.
[Objective]The response of the radial growth of Picea koraiensis to climate change was studied by using the radial growth and climate factors of Picea koraiensis in Xiaoxing'an Mountains.[Method]The methods of the chronology characteristics of Picea koraiensis in Xiaoxing'an Mountains,ring index characteristics,and Pearson correlation test were used.[Result]The radial growth of Picea koraiensis was significantly negatively correlated with the temperature at the end of the previous year's growing season(September),the current year's growing season(June),and the end of the current year's growing season(September);The radial growth of Picea koraiensis was significantly positively correlated with the monthly minimum temperature in the winter(February)and the monthly average temperature in the early growing season(April)of the current year.Precipitation had little effect on the radial growth of Picea koraiensis.The correlation between the radial growth of Picea koraiensis and the temperature at the end of the growing season(September)of the previous year had changed from a significant positive correlation before the temperature rise to a significant negative correlation after the temperature rise;The correlation between the radial growth of Picea koraiensis and the precipitation at the end of the previous year's growing season(September)and the end of the current year's growing season(September)had changed from a negative correlation before the temperature rise to a significant positive correlation after the temperature rise.The relationship between the radial growth of Picea koraiensis and the precipitation before the growing season(March)changed from a positive correlation before the temperature rise to a significant negative correlation after the temperature rise.[Conclusion]Temperature was the main limiting factor for the radial growth of Picea koraiensis,the inhibitory effect of temperature increase on tree growth was strengthened.
The development of forest resources survey and monitoring equipment is helpful to improve the efficiency and accuracy of forest resources monitoring,which is the objective requirement of forestry ecological construction in the new era,the inevitable choice to strengthen forest resources supervision,and the fundamental need to improve the level of forest management.This paper analyzed the current situation and development trend of forest resource survey equipment development,and analyzed the lightening,integration and integration needs of forest resource survey equipment development with three cases.Based on the practice of forest survey,the invention solution is provided to reduce the load of equipment of investigator and improve the efficiency of investigation work,which aims to improve the level of forest management and meet the needs of modern forestry development.
[Objective]Seeds are important foundation and carrier for plant reproduction.The morphological characteristics and germination rules of Acer truncatum seeds were explored to reveal the morphological characteristics and variations of Acer truncatum seeds and the germination rules of seeds,which could provide scientific basis for cultivating high-quality Acer truncatum seedlings.[Method]Using the Acer truncatum seeds from seed production stands in the Songshushan Mountain,Inner Mongolia,the morphological characteristics(long diameter,wide diameter,longitudinal diameter,shape index,size index,1 000 grain weight,etc.)of seeds were accurately measured.The allometry growth relationship of seed morphological characteristics was also analyzed using the standardized major axis estimation method.The seed germination law was then observed by means of paper germination in petri dish.[Result]The average length diameter of Acer truncatum seeds was 10.20±0.76 mm,the wide diameter was 6.77±0.40 mm,the longitudinal diameter was 4.32±0.58 mm,the shape index was 1.51±0.12,the size index was 69.10±0.51,and the 1 000 grain weight was 154.02±4.50 g.The length diameter,width diameter,shape index,and size index all distributed normally.The variation coefficients of width diameter and longitudinal diameter were 6%and 13%,respectively;while the variation coefficients of other traits were lower than 10%.Significant allometry growth relationships were observed among the length,width and longitudinal diameter of seeds.Specifically,the relative growth rate of width and diameter decreased with the increasing length and diameter.The relative growth rate of longitudinal diameter increased with the increasing long diameter.As the width diameter increased,the relative growth rate of the longitudinal diameter increased,and the seed length played a relatively dominant role in the seed morphological characteristics.The seed germination rate of Acer truncatum was 90.75%±1.89%,the seed germination potential was 47.50%±4.80%,the germination index was 18.94±0.78,and the average germination time was 6.11±0.57 days.The peak period of seed germination was 3-11 days,and the seed germination rate reached 84.75%±0.96%at the end of the peak period.[Conclusion]The Acer truncatum seeds is shaped like an irregular flat ball.The smaller the seeds are,the rounder they are when viewed from a two-dimensional perspective.However,the larger the seeds are,the rounder they are when viewed from a three-dimensional perspective.The maximum variation in seed longitudinal diameter can be utilized in seed quality grading.Meanwhile,the germination process of Acer truncatum seeds can refer to 11 days,and the germination rate can reach 85%in actual production.The results can be used to guide production practice and promote the high-quality development of the sexual reproduction of Acer truncatum.
[Objective]To analyze the trap effect of Hyphantria cunea,so as to choose the best trap method and improve the control effect of Hyphantria cunea.[Method]Taking Hyphantria cunea as the main research object,three treatments were set,namely different plant volatiles,different band LED lamp and different trapping time,to analyze the effects of different treatments on the trapping effect of Hyphantria cunea.[Result]The 6-methyl-5-heptene-2-one and β-basil formulated in 7:3 ratio can improve the trapping effect of Hyphantria cunea,and the attracting rate can reach 28.32%;360-365 nm band LED lights can achieve better trapping effect,attracting moth rate can reach 61.97%;Trapping at 02:00-04:00 can achieve good trapping effect,and the rate of attracting moths can reach 28.13%.[Conclusion]During the period of 02:00-04:00,6-methyl-5-heptene-2-one and β-roletene prepared in accordance with the ratio of 7:3,combined with the use of 360-365 nm band LED lights,the trapping effect of Hyphantria cunea reached the best.
