The purpose of this trial is to compare the different stress tolerance effects of Dora chitosan oligosaccharide powder.
We setted 6 groups in this trial, each group has 5 plants.
Group A1: Control group with water in drought
Group A2: Control group with water in waterlogging
Group A3: Control group with water in salinization
Group B1: 150ppm Dora Chitosan Oligosaccharide in drought
Group B2: 150ppm Dora Chitosan Oligosaccharide in waterlogging
Group B3: 150ppm Dora Chitosan Oligosaccharide in salinization
Before the lettuce seeds were sowed in seedling trays, they needed to be sterilized with 75%(v/v) alcohol for 15 minutes, and washed with distilled water 3 times. One pot with one plant, on the 1st and 10th day after transplanting, the plants were watered with clear water and 150ppm COS solution respectively. 14 days later, stress simulation treatment was started.
1. Drought: From day 14 to day 22 after transplant, maintain the soil at a low moisture level.
2. Waterlogging: On the 14th day of transplanting, the water layer was kept at 2 cm and maintained for 4 days. Then after applying clear water and 150ppm chitosan oligosaccharide solution, respectively, the waterlogging state continued for 4 days.
3. Salt stress: From the 14th day of transplanting, each pot of root irrigation contains 150ml of NaCl solution with a concentration of 4%(w/v) and this state of salt stress maintains for 4 days. Continue to maintain the salinity state for 4 days.
The plants were harvested after treatment and the relative water content, plant height, stem diameter, and plant weight of the plants were measured.
Measure the weight with a balance, measure the lettuce height with a ruler, and measure the stem thickness with a vernier caliper.
The relative water content of the plant can be calculated: (X1-X2)/(X3-X2)
X1: the fresh mass except for the roots
X2: the mass after the greening at 105℃ for 15 minutes, and then dried at 80℃
X3：the mass is immersed in distilled water at 4℃24h to obtain when saturated with water
Photographs were taken to record the growth of the lettuce, and the groups can be compared.
Trial Results
1. Effects of chitosan oligosaccharide on lettuce growth in drought stress
1.1 Plant height: The difference between group A and group B is very small.
1.2 Stem diameter: Group A: 6.08mm. The treatment group: smaller. The overall difference was not very large in early times because the stem of lettuce seedlings was thinner.
1.3 Plant weight: The treatment group was greater than the control group with a more weight of 9.44g.
1.4 Relative water content of plants:
X1: the fresh mass except for the roots.
X2: the quality after 15 minutes of curing at 105°C and drying at 80°C.
X3: the mass when immersed in distilled water at 4°C for 24 h to obtain saturated water.
The relative water content of plants is (X1-X2)/(X3-X2). This is one of the indicators reflecting the osmotic regulation function and drought resistance of plants. The relative water content of the plants in the control group was 65.10%, and the relative water content of the plants in the B group was 71.32%, which was 6.22% higher.
2. Effects of chitosan oligosaccharide on lettuce growth in waterlogging stress
2.1 Plant height: The difference between group A and group B is less.
2.2 Stem diameter: The overall difference was not very large in early time, but the main stem of group B was wider than group A.
2.3 Plant weight: The weight of the lettuce in the treatment group was greater than the control group, with 6.66g weight more.
2.4 Relative water content of plants: The control group is 39.30% and the B group is 70.19%, which was 33.89% higher. The difference is obvious.
3. Effects of chitosan oligosaccharide on lettuce growth in salinization stress
3.1 Plant height: Group B the seedlings were under the treatment of COS powder(150ppm) is higher than group CK.
3.2 Stem diameter: There are no obvious differences between group A and group B.
3.3 Plant weight: It was 33.08g chitosan oligosaccharide powder(150ppm) in group B, which had more 4.68g growth advantages over the control group.
3.4 Relative water content of plants: The relative water content of the plants in the control group was the lowest at 69.23% while group B which was treated with Dora Chitosan Oligosaccharide powder(150ppm) was the highest at 79.92%.
At Last,
1. For drought stress, we can see from the plant weight that Dora chitosan oligosaccharide powder(150ppm) plays a certain role in promoting an effect on relative water content.
2. As for the experiment of waterlogging, Dora COS powder(150ppm) has the ability to maintain the water content and weight of the plants, although the plant height is not obvious from the appearance.
3. From the plant weight and relative water content, we can see that chitosan oligosaccharide powder(150ppm)has a good anti-salinization effect.
To sum up, Dora chitosan oligosaccharide has a good ability to help lettuce plants defend against stress such as drought, waterlogging, and salinization. From the aspects of plant weight and relative water content, Dora's chitosan oligosaccharide has a good performance. As a consequence, we recommend applying Dora chitosan oligosaccharide to promote plants' abilities to resist abiotic stress, the final dosage is 150ppm.
If you want to know more trial data and results of our Dora chitosan oligosaccharide, please contact us.