Effect of different pre-sowing treatments on seed germination percentage and growth performance of Acacia auriculiformis

Seed morphology,germination and seedlings growth of Acacia auriculiformis were studied.The experiment was conducted in the nursery of Forestry and Wood Technology Discipline,Khulna University,Bangladesh.Matured seeds of the species were collected from healthy trees of road side plantation from different areas of Khulna District,Bangladesh and treated with five pre-sowing treatments（control,immersion in cold water,immersion in hot water,scarification with sand paper and immersion in concentrated H2SO4）.The average length,breadth and thickness were found to be（0.58±0.017） cm,（0.44±0.007） cm and（0.20±0.089） cm,respectively.Germination was conducted in polybags with a mixture of top soil,coconut husk,coarse sand,and fine sand in a ratio of 3：4：1：1.Results reveal that pre-sowing treatments influences the germination rates of seeds that significantly increase the percentage germination compared with those in control（43%） and cold water treatment（52%）.The highest germination success rate was found 83% in hot water treatment followed by 78% in scarification with sand paper,and 75% with immersion in H2SO4.Germination started from 7 to 12 days and completed between 28 and 35 days period in all treatments.ANOVA showed the significant difference（p0.05） among the treatments in seed germination,but no significant difference among treatment with regard to starting day,closing day and total germination period.In case of height and diameter growth,seedlings originated from the seeds with hot water treatment shows significantly higher in wet season（from May to July）.Hot water treatment can be recommended on seed germination of the species in rural Bangladesh.

Effect of pre-sowing treatments on germination and initial seedling development of Albizia saman in the nursery

Albizia saman （Jacq.） F. Muell. commonly known as rain tree seeds were treated with five pre-sowing treatments to study the effect of pre-sowing treatments on germination and initial seedling development in the nursery.The experiment was established in the nursery of the Institute of Forestry and Environmental Sciences.University of Chittagong, Chittagong, Bangladesh. Results revealed that Nail clipping in one side of the seed （at the distal end of the seed） （T4） provides the highest （50%） seed germination. The second highest germination （42%） was obtained for the seeds treated with immersion in cold water for 24 h （T1）. Germination was completely inhibited when the seeds immersed in boiled water for 30 s followed in cold water soaking for 24 h. Other germination parameter and initial morphological growth and biomass production of the seedlings was also higher for the treatments T4and Ti in comparison to the control （Ta）treatment. Pre-sowing treatments of T4 e.g. Nail clipping in one side of the seed （at the distal end of the seed） and T1 （Seeds immersed in cold water for 24 h） may be recommended for maximum germination and initial vigorous seedlings growth of Albizia sarnan in the nursery.

Standardized pod collection time, pod length and pre-sowing treatment of Albizia lebbeck at terai zone of West Bengal, India

Three pod lengths （ 10 cm, 10–20 cm and 20 cm） and 13 pre-sowing treatments were considered with four dates of collection （9 February, 19 February, 1 March and 11 March） to investigate their effect on germination rate and growth of seedlings of Albizia lebbeck （L.） Benth. at Pundibari, West Bengal, India. The best time of pod collection was on 19 February as the germination rate of the seeds collected on this date was 92.5% without requiring any pre-sowing treatments. This clearly indicated that the seeds collected on 19 February were non-dormant, viable and physiologically mature. Significantly better seedling growth was also obtained when the seeds were sown on 19 February which was extracted from pods of length 10-20 cm. Application of thio-urea as a pre-treatment did not significantly enhanced seed germination rate, but its application in lower concentration （100 μL·L-1） resulted in better seedling growth and development.

Effects of pre-sowing treatments on seed germination of Melia azedarach

A germination experiment of pre-treated seeds of Melia azedarach was conducted in the nursery of Forestry and Wood Technology Discipline,Khulna University,Bangladesh.Matured seeds of Melia azedarach were collected from healthy trees of National Botanical Garden,Bangladesh and were treated with five pre-sowing treatments（control,immersion in cold water,immersion in hot water,scarification with sand paper,and immersion in concentrated H2SO4） on seed germination.Results revealed that the germination rates of pre-sowing treated seeds were significantly increased compared to those in control,except for cold water treatment.The highest germination success（80%） was found in scarification with sand paper,followed by 74% and 69% in immersion in H2SO4 and hot water treatment,respectively.Germination started on 8-11 days and completed on 20-21 days of the germination period in all cases.Analysis of variance showed the significance difference in germination success among the treatments but no significance difference in germination period among the treatment.Hot water treatment may be recommended on seed germination of the species in rural Bangladesh.

Design and test of a double compression seeder for pre-sowing and seed furrow of wheat in wide-seedling belts

To solve the problem of poor sowing quality due to loose soil in wheat seedbed after land preparation in the Huang-Huaihai region of China,a double compression seeder for pre-sowing and seed furrow of wheat in wide-seedling belts was designed.The machine sowing operation was divided into two processes:pre-sowing compression and seed ditch compression,pre-sowing compression was carried out homogenization of the pre-sowing seed bed that the tractor wheel has crushed,and the seed ditch compression compresses the seeds and soil in the seed ditch,so that the seeds were embedded in the seed ditch soil.By analyzing the kinematics of the pre-planting compression device and the spiral blade in the process of soil levelling and compression,the structure of the equal-difference variable-diameter equal-pitch spiral conveying winch was designed,and the key parameters of the drum spiral blade were determined,and then the height of the spiral blades,the rutting distance and the speed of the compression roller were taken as the test factors,and the soil flatness was used as the index to carry out the discrete element simulation test.The simulation results show that when the spiral blade was 4.85 cm,the rut distance was 37.4 cm,and the rotation speed was 327.16 r/min,the optimal land flatness was 0.18.Finally,field experiments were carried out on the seeder,and the results showed that:the soil bulk density after operation was 22.7%greater than that before sowing(p<0.01),and the soil flatness was 1.9 cm,which was consistent with the simulated results.The use of pre-sowing compression and seed furrow compression methods improved the soil environment of the seed bed,increased the uniformity of the seeding depth,and promoted the root growth of wheat.This study provides equipment support and technical reference for agricultural production in wheat-corn rotation areas in the Huang-Huaihai region of China.

Study on laser pre-sowing treatment of rice seeds by free-falling transport method

Recently,laser pre-sowing treatment of seed is attracting a great attention of scientific community for its positive influence to enhance germination,seedling and growth of plants,vegetables and crops.In this study,effect of laser pre-sowing treatment of rice seeds was given,which was implemented by free-falling transport method.Test has been processed in Unzon district(DPRK)in 2017.Two kinds of Korean rice seeds(namely Pyongyang-53 and Dongsung-1)were irradiated by semiconductor laser with wavelength of 650 nm,which was controlled in PWM mode.Each group was irradiated using exposure time of 0.28 s and duty ratio of 50 percent.In result,a considerable improvement has been observed in germination,growth and final productivity.Using laser pre-sowing treatment of rice seed,total productivities have been increased by 7.7%and 21%for “Pyongyang-53”and “Dongsung-1”,respectively.Results show that laser pre-sowing treatment of seed can significantly enhance germination,seedling and growth,and thus can improve the productivity of rice.In future research,laser pre-sowing treatment by free-falling transport method should be processed for other kinds of plants,vegetables and cereal crops to find out appropriate parameters,such as mechanical structure of device,wave length and power of laser,frequency and duty cycle of PWM control signal and exposure time,etc.

Depulping of Fruits and Soaking the Seeds Enhances the Seed Germination and Initial Growth Performance of <i>Terminalia belerica</i>Roxb. Seedlings

The study describes the effects of depulping the fruits and soaking the seeds of Terminalia belerica Roxb. on seed germination and seedling growth in nursery condition. Around half of the freshly collected fruits of T. belerica were depulped by rotting the fleshy pulp in water. Depulped seeds or intact fruits were dried in sun following storage in airtight container. Effects pre-sowing treatments were explored by soaking the dry intact fruits or depulped seeds in cold water for 0, 24, 48 and 72 h and sowed in polybags filled with soil mixed with decomposed cow dung. The study revealed that depulping of fruits and soaking the seeds significantly enhanced the seed germination and seedling growth performance in nursery condition. The fastest seed germination was observed in depulped seeds soaked in cold water for 72 h (DT3) and slowest germination was in intact fruits without treatment (IT0). The highest germination percentage (93) was observed in depulped seeds soaked in cold water for 48 h (DT2) followed by 85.6% in depulped seeds soaked in water for 24 h (DT1), which was significantly higher than the other treatments including the control (36.7). Although growth parameters such as shoot length, root length, total height, leaf number, leaf area and collar diameter of the seedlings were maximum in the seedlings developed through DT3, the vigor index was maximum in DT2 and minimum in IT0. Total dry mass per seedling was also maximum in the seedlings developed from the treatment DT3. Considered the imbibition period, germination percentage, growth performance including vigor index and total biomass produced per seedling, depulping the fruits and soaking the dry seeds in cold water for 48 h was recommended for obtaining maximum seed germination and seedling growth performance.