VIETNAM NATIONAL UNIVERSITY OF AGRICULTURE FACULTY OF BIOTEACHNOLOGY GRADUATE THESIS TESTING THE EFFECT OF AMOMUM SUBULATUM EXTRACT ON THE LARVAE OF PIERIS RAPAE Practicing Student : Nguyen Dinh Thinh Class : K61-CNSHE Tutor : Dr. Dang Thi Thanh Tam HA NOI - 2021 COMMITMENT I hereby declare that this thesis is composed of my original works and contains no material previously published or written by another person. I commit that the references in the thesis are citied and all the help are thanked. Hanoi, January 28th 2021 Student Nguyen Đinh Thinh i ACKNOWLEDGEMENTS First and foremost, I have to express my appreciation and big thanks to the the Director of Vietnam National University of Agriculture , Faculty board and teachers in the Department of Plants Biotechology for creating an interesting learning environment and providing me priceless knowledge through five academic years.
During the time doing this thesis, many people helped me in bringing this work to existence, especially my supervisor Dr. Dang Thi Thanh Tam, who supported and inspired me to accomplish this thesis.Without her precious support it would not possible tocomplete this thesis successfully. I would like thank my partner Trinh Thi Huong Tra and all my friends , who were by my side to help and give me all best conditions. Last but not least, I am also grateful to thank my parents for supporting and encouraging me spiritually throughout my thesis and my life in general.
Hanoi, January 28th 2021 Student Nguyen Đinh Thinh ii CONTENTS COMMITMENT. iii LIST OF TABLES. v LIST OF FIGURE. Overview of Pieris rapae.
Life Cycle of Pieris rapae. The damage of Pieris rapae. Some research on Pieris rapae. Overview of Amomum subulatum plant.
Distribution and Habitat. Benefits of Amomum subulatum plant. MATERIALS AND METHODS. Location and time of the study.
Time of the the study. Instruments, chemicals and analytical equipment. Pieris rapae culture. Amomum subulatum extract preparation.
RESULTS AND DISCUSSIONS. Testing the toxicity of Amomum subulatum extract on Pieris rapae larvae. Testing the antifeeding effect of Amomum subulatum extract on P. CONCLUSIONS AND SUGGESTION.
36 iv LIST OF TABLES Table 3. Diluting a starting stock solution to create solutions at various concentrations. Mortality rate of larvae in the treatment with Amomum subulatum. Leaf consumption rate of larvae in the treatment with Amomum subulatum.
Deterrency percentage of leaf consumption value of larvae after 24 hours. 30 v LIST OF FIGURE Figure 2. Life cycle of Pieris Rapae. Young caterpillars of Pieris rapae were causing damage on cabbage plants.
Morphological characteristics of Amomum subulatum. Amomum subulatum plants are grown in Vietnam (Ha Giang). The process of growing cabbage. The process of Pieris rapae culture.
The process of reparing for Amomum subulatum extract. The process of testing the toxicity of Amomum subulatum extract. The process of testing the antifeeding effect of Amomum subulatum extract on P. Mortality rate of larvae in the treatment with Amomum subulatum after 48 hours.
Experiment at initial time and after 48 hours. The consumption area between control and treatment sample at 0. Control and treatment sample at initial time and after 24 hours at 0. Introduction In the past 30 years , scientists have been intensively investigated about plant-derived extracts and phytochemicals with the main purpose was an effort to develop alternatives to conventional insecticides with reduced environmental impacts and protected people's heath.
Synthetic insecticides can leave potentially toxic residues in food products and be deleterious to non-target organisms. Every year, the crop losses due to pests may reach 10–20%. In Vietnam, the overuse of some chemical classes of insecticides has led to environmental and human health problems.Synthetic chemical insecticides have many harm that endangering human health and the environment such as effects on the health of applicators, farmers, and even consumers; it accidentally kills wildlife ,beneficial insects, including pollinators and espiecial pollutes underground water. From the drawbacks of chemical insecticides and their discontinued manufacture have spurred scientist study and search for biological pesticides with the ingredient that are found in products of natural origin.
The botanical- based pesticides often good for user, no harmful with other organisms. Plantbased bio-pesticides are generally thought to be more selective, be less harmful to nontarget organisms, degrade quickly, and be less phytotoxic. Therefore, botanical insecticides may be effective for managing the small white butterfly, Pieris rapae which is an important pest that affects cruciferous crops worldwide. A single female lays 300 eggs on average, but clutches may include close to 1000 eggs.
Each young larvae occupies an outer leaf of a cabbage for feeding. Older larvae move onto inner cabbage leaves and into cabbage heads by eating outer leaves of the cabbage head and gnawing into it. Plants soiled with excrement rot easily. In the world, some scientists have the study using plant extracts to protect some of vegetables from larvae of Pieris rapae such as R.
XU et al.( 2008) performed a study about the control effects of pumpkin leaf extract 1 on caterpillars of the small cabbage butterfly and the result showed feeding restrain, at concentration 1. In the presence of pumpkin extract, feeding of larvae will decrease and the impact on crops will be limited. Beside , Hasheminia et al.(2013) conducted a study about effect of Milk Thistle, Silybium marianum extract on the small white butterfly with toxicity tests and the result showed that LC50 and LC25 values were 2. With using plant extract helped to reduce number of larvae of Pieris rapae that damaged the plant.
In Vietnam, farmers used many ways to control larvae of Pieris rapae. With manual ways, they used racket to catch butterfly and young caterpillar beside they grown some types of plant that can be ability repel the butterfly.But the most popular way ,they used chemical pesticides to kill young caterpillar that would bring the active effects and effect quickly and in a timely manner. It is this way of control P.rapae larvae of Vietnamese farmers, leading to harm to human health, environmental pollution, and ecological impacts and with the benefits pesticides of biological origin will bring us and the environment, I think we should regularly use them. From the above bases, I always have the desire to find new directions and especially it can be applied in Vietnam with the following criteria easy to implement, cheap price, abundant raw materials and high efficiency.
I have learned and knowed that Amomum subulatum plants were used for many different purposes, especially research on insecticide, antibacterial (Satyal et al., 2012), antifungal and antioxidant activities ( Kapoor et al. Besides Amomum subulatum plants are quite popular in Vietnam, the price is quite cheap, easy to buy and convenient to use. As a consequence, I want to find the plant extracts that have highly effective insecticide on Pieris rapae. I decide to choose the subject: “Testing the effect of Amomum subulatum extract on the control of larvae of Pieris rapae.
2 In this research, the toxicity and antifeeding effects of Amomum subulatum extract on Pieris rapae were tested. Aims Testing the effect of Amomum subulatum extract on the control of larvae of Pieris rapae. Objectives Testing the toxicity of Amomum subulatum extract on young caterpillars. Testing the antifeeding effect of Amomum subulatum extract on young caterpillars.
Overview of Pieris rapae Pieris rapae is a small- to medium-sized butterfly species of the family Pieridae. It is known in Europe as the small white, in North America as the cabbage white or cabbage butterfly, on several continents as the small cabbage white. This species is widely distributed throughout Europe, North Africa, Asia and is a pest to crucifer crops such as cabbage, kale, bok choy and broccoli. Pieris rapae is easily confused with other common cabbage white butterflies: Pontia protodice, Pieris napi; and Ascia monuste (Shen et al.
Scientific Classification Pieris rapae (Linnaeus) (Insecta: Lepidoptera: Pieridae) Kingdom: Animalia Phylum: Arthropoda Class: Insecta Order: Lepidoptera Family: Pieridae Genus: Pieris Species: P. Rapae Binomial name: Pieris rapae 4 2. Life Cycle of Pieris rapae Eggs of Pieris rapae Larvae of Pieris rapae Adult butterfly of Pieris Rapae Pupa of Pieris Rapae Figure 2. Life cycle of Pieris Rapae Life Cycle of Pieris Rapae The complete life cycle of Pieris rapae requires three to six weeks and depending on weather.
The number of generations reported annually are two to three in Canada, three in the New England states, three to five in California, and six to eight in Vietnam. Imported cabbageworm can be found throughout the year in Vietnam and the most quantity at time from autum to winter when the source food is plentiful (Shen et al. Eggs: Eggs are laid singly, usually on the lower surface of outer leaves of plants. The egg measures 0.5 mm in width and 1.0 mm in length, and initially is 5 pale white in color but eventually turns yellowish.
They have shape is described as resembling a bullet. Larvae: The larva is green, velvety in appearance, and bears five pairs of prolegs. The instar have five stages of ages.The body length are about 0. Body lengths at maturity of each instar averages from 2 to 3 cm respectively.
The larvae requires about 15 days (range 11 to 33 days) to complete its development. The best condition to develop at 20 - 24°C temperature and 75% - 85% humidity. A way to discriminte the first instar with all larval stages don't have a narrow yellow line running along the center of the back. Pupa: Pupation normally appears on the food plant, but cabbageworm may pupate everywhere are places that larvae can clingand nearly source food.
The pupa is about 18 to 20 mm in length, varies in color, usually yellow, gray, green and speckled brown. At pupation, the chrysalis is anchored by the tip of the abdomen to the silk pad and a strand of silk is loosely spun around the thorax. In Vietnam they develop all season in year. The pupation is the overwintering stage, however, its duration may be prolonged for months that depend on temperature.
The proportion of pupae that diapause increases as winter progresses, so that at the time of the final generation all pupae are in diapause as winter progresses so that at the time of the final generation all pupae are in diapause. Adult: Upon emergence from the pupa, the butterfly has a wing span of about 4. It is white above with black at the tips of the forewings. The front wings are also marked with black dots, two in the central area of each forewing in the female and one in case of males.
When viewed from below, the wings generally are yellowish and the black spots usually show faintly through the wings. The hind wing of each sex also bears a black spot on the anterior edge. The body of the butterfly is covered with dense hair which is colored 6 white in females but darker in males. The adult typically lives about three weeks.
The female produces 300 to 400 eggs. The adult is very active during the daylight hours and often moving from the crop to flowering weeds to feed. The damage of Pieris rapae. Young caterpillars of Pieris rapae were causing damage on cabbage plants Larvae of Pieris rapae damage cruciferous crops by eating leaves, veins and tips of plants.
Young larvae hatch on the outer leaves and feed on them superficially leaving the upper leaf surface intact. Older larvae make holes in the leaves and are more likely to eat through small veins, they also damage the outer leaves of the hearts of cabbages or the curd of broccoli or cauliflowers. They often bore into the top of plant damaging the edible portion. Heavily infested plants become ragged and stunted, leading to the plant can not growth and some case can die.