summary of agricultural doctoral thesis studying the growth, development capacities and technical measures to increase yields, qualities of some exotic orchid cultivars (cattleya, dendrobium, oncidium) for nort

AND TRAINING AND RURAL DEVELOPMENT VIETNAM ACADEMY OF AGRICULTURAL SCIENCES HOANG XUAN LAM STUDYING THE GROWTH, DEVELOPMENT CAPACITIES AND TECHNICAL MEASURES TO INCREASE YIELDS, QUALIT

AND TRAINING AND RURAL DEVELOPMENT

VIETNAM ACADEMY OF AGRICULTURAL SCIENCES

HOANG XUAN LAM

STUDYING THE GROWTH, DEVELOPMENT CAPACITIES AND TECHNICAL MEASURES TO INCREASE YIELDS, QUALITIES OF

SOME EXOTIC ORCHID CULTIVARS (CATTLEYA, DENDROBIUM,

ONCIDIUM) FOR NORTHERN VIETNAM

Branch of study: Crop science Code : 62 62 01 10

SUMMARY OF AGRICULTURAL DOCTORAL THESIS

HANOI - 2014

Project completed at:

VIETNAM ACADEMY OF AGRICULTURAL SCIENCES

Scientific supervisors: 1 Ass Prof Dr Nguyen Thi Kim Ly

2 Prof Dr Nguyen Xuan Linh

Vietnam Academy of Agricultural Sciences

At hours, day month year

This thesis can be referred to at:

- Vietnam National Labrary

- The Libray of Vietnam Academy of Agricultural Sciences

INTRODUCTION

1 Urgency of research topic

Of all popularly planted types of flowers, orchids are known as a flower not only beautiful, fragrant, multi – colorful, but also are of high economic value So far, mankinds have learned on more than 750 orchid branches with 35000 wild orchids species and 75000 orchid cultivars as a result of selection and breeding [33]

In Vietnam, there are about 1003 species of orchids available [ 33 ] These are very abundant plant resources to serve the creatation and breeding of new varieties of orchids However, most of these orchids can only be exploited and cultivated in natural conditions, technical measures have not yet been applied, so their yields and qualities are not high that can not meet the requirements of consumers Whereas the exotic orchids have their advantages as having good growth and healthy development, high yields , good quality of flowers: big flowers, beautiful colors, various diversified, durable and long -lasting flowers and that their flower blooming time can be controlled for the occasions of Holidays or Lunar New Year Celebration, that has brought about high economic efficiency to growers

Cattleya, Dendrobium, Oncidium are pretty orchids species popularly esteemed by the markets It is attractive to consumers with diversified colors, beguiling aroma and especially, commercial producers are attracted by the durability of flowers However, the actual production of these orchids in Vietnam still faces many difficulties Lan Cattleya, Dendrobium , Oncidium orchids are very suitable the climate in Southern areas as of its all - year-round warm weather, great sun radiation and long appropriate sunlight for plant to grow and develop, whereas the climatic condition in the North is not favorable due to high summer temperatures (33 - 380C), high humidity and high sunlight intensity that causes a negative impact to the growth of the plants, making the plants susceptible to leaf blight, high percentage to rotten disease prevalence In Winter, the temperatures is too low, weak sunlight intensity, short sunlight during the days are also not favorable for plant growth , development and giving flowers On the other hand, as for lack of good seeds, technical inconsistency and inappropriate caring process the production cuold not bring about high efficiency, quantity and quality of orchids still can not meet consumer requirements, while the demand for the above mentioned orchids is very high In order to overcome this limitation, enabling plant orchids in general and Cattleya, Dendrobium and Oncidium orchids in particular to

develop to be effective, the research subject " Studying the growth, development and technical measures to increase productivity, quality of exotic orchid varieties (Cattleya , Dendrobium , Oncidium ) for Northern Vietnam "

2 The purpose and requirements of the subject

2.1 Purpose

- The purpose of this research subject is to study the growth, development of some exotic hybrid orchid genera of Cattleya, Dendrobium, Oncidium in order to select new promising hybrid orchid cultivars, consistent with the Northern Delta region and the nearby region with similar ecological conditions

- To determine the impact of growing conditions and technical factors to the growth, development, flowering of some exotic hybrid orchid genera as Cattleya, Dendrobium, Oncidium and to propose appropriate technical measures, applying effectively to production that contribute to the development of growing orchids in the Northern Delta

2.2 Requirements of the research subject:

- To evaluate the adaptability of exotic orchids belonging to 3 branches of Catlleya, Dendrobium and Oncidium (survival, growth and development capabilities) in the period of nursery and in production gardens in order to select some new promising orchid cultivars adaptable to ecological conditions of the Northern Delta region

- To study the effect of growing conditions (substrate, fertilizers, shading system, flowering control) to the growth and development of selected hybrid orchids in order to identify appropriate technical measures that help reaching high yield, high quality of flowers for these orchids

3 Scientific and practical significances:

3.1 Scientific significance

- The results of the study subjects have provided the scientific data on basical criteria for an orchid to reach high yield, good quality as well as the influence of growing conditions (temperature, light, substrate, fertilizer, ) to the growth, development and the formation of flowers and flower quality of the Cattleya orchid, Dendrobium, Oncidium in Northern Delta conditions

- The study results are also references of great value for teaching, research and production of orchid plants in general as well as Cattleya, Dendrobium, Oncidium in particular

3.3 The Novelty of the thesis

- Having fully and systematically studied the morphological characteristics , growth and development for an orchid to gain high yield and quality On that basis,

3 hybrid orchid cultivars of Cattleya, Dendrobium , Oncidium with good prospects for growth, development, good flowering in the condition of Winter - Spring season in the Northern Delta region, have been selected for the production of hybrid orchids

- Having studied systematically the growing conditions and technical measures for eachcrop season for 3 orchid genera of Cattleya orchid, Dendrobium, Oncidium, in order to increase survival rate of seedling and to reduce the incidence

of soft rotten disease in nursery stage in hot and humid summer climate condition

At the same time, it helped to increase the rate of flowering of the plants as well as flower quality blooming in cold winter conditions of the Northern Delta region

4 The structure of the thesis

The main contents of the thesis are presented in 139 pages (excluding references and appendices) Introduction: 4 pages; Chapter 1: Overview document:

40 pages, Chapter 2: Materials, research content and methodology: 17 pages; Chapter 3: Research Results and Discussion: 76 pages; Conclusion and proposals: 2 pages The dissertation consists of 37 tables, 19 form, 50 Vietnamese documents,

72 documents in English The appendix includes photos of selected orchids in the experiments, statistical analysis results and experimental data processing and contents related to the thesis

Chapter 1 OVERVIEW

1.1 General Overview of the orchid Cattleya , Dendrobium , Oncidium

Cattleya (Cattleya orchids) includes about 65,000 primitive species and numerous outvarietal and intervarietal crossed species They are native to tropical America, mostly in the mountains with altitude from 600 - 1800 m [46]

Dendrobium (Hoang Thao orchid) is the largest genus in orchid family, consisting of over 1,600 species whose distribution stretches from Korea, Japan, Indonesia to Australia In Vietnam, over 200 species of orchid Dendrobium has been recorded [ 94 ]

Oncidium (dancing lady) consists of about 400-600 species originating from the America and subtropical regions They can be found from Florida to the Bahamas, Caribbean Islands and southern Mexico, Central and South America to Argentina [122]

By studying botanical characteristics and for external requirements for Cattleyas, Dendrobium, Oncidium, it is shown that climatic condition of Vietnam can absolutely be suitable for the culture of this species, particularly in the provinces of the Southern region However, because of the cold weather in the northern provinces, the plants are less developed and grown To develop this orchid

in production, it is necessary to pay special attention to the uses of substrates, fertilizers, growth regulators, flowering stimulants and flowering control measures

on the occasions of Tet and Holidays

1.2 The status on production and consumption of Cattleya, Dendrobium,

Oncidium orchids in the world and in Vietnam:

Export markets of orchids on the world are ever-expandin European Union (EU), North America and Japan are still biggist areas to consume most cut- orchids, although China is also becoming an important market Only 25 countries of the EU

on average have spent 13.7 billion USD/year (CBI, 2007) for consumer cut-

orchids, mainly Dendrobium and Oncidium, accounting for over 50% of total

orchid consumption Of which, Germany topped with the expendicture of about 3 billion euros per year The folowing 5 countries with high demand are the UK (2.82 billion ), France (1.85 billions), Italy (1.62 billions), Spain (0.99 billions) and the Netherlands (0.89 billion ) [ 118 ] Japanese consumer demand by 5.4 million/year

on cut orchid, U.S: $ 5.5 billion [119] It can be said that orchid production has brought about very highly profits for developed and developing countries Besides, Cattleya, Dendrobium, Oncidium account up for the bulk of total production and consumption of orchids in the world This proves that these flowers bring high economic efficiency to growers and preferred by consumers

Cattleya, Dendrobium, Oncidium are common orchids genera which bring high economic efficiency for the orchid production branches of orchid growing countries over the world In recent years, thanks to the expansion of production and development of these orchids, significant economic benefits have been brought about to countries such as Thailand, Taiwan, Singapore, China With similar climatic conditions to these countries and experienced growers, the Cattleya, Dendrobium, Oncidium orchid genera can be grown and fully developed in Vietnam

Orchid growing area in Vietnam is t at modes level, only accounting for 10

% of the flowers growing areas [23] Production of orchids in Vietnam concentrates

to a promising future for development of these flowers basing on the existing favorable conditions for the development of orchid growing branch

1.3 Status of research on Cattleya, Dendrobium, Oncidium orchids in the world and in Vietnam:

1.3.1 Status of research on Cattleya, Dendrobium, Oncidium orchids in the world

For many years, due to high economic and aesthetic values of orchid plants, that developed countries in the world have used traditional techniques and modern methods for breeding and selecting flowers in general and for orchids in particular and have achieved very satisfactory results, especially on some industrial orchids

as Dancing lady (Oncidium), Hoang Thao (Dendrobium), Cat (Cattleya) and some other orchids and these have brought about big financial resources for orchids producing branches in countries as Netherlands, China, Taiwan, Thailand

The above results show that the world has had a lot of research work on orchid plants, in general and on the genera of Cattleyas, Dendrobium and Oncidium, in particular The study focused on a number of areas such as plant breeding and seed multiplication, technical planting measures and measures for pests and diseases preventions,

1.3.2 Status of research on Cattleya, Dendrobium, Oncidium orchids in Vietnam

In Vietnam, there have been many studies on collectioconservation the genetic resources of native orchids and exotic cultivars as well as evaluation and selection

of promising orchid varieties for production and concentrate to study technical measures on substrates, fertilizers, flowering control techniques, pest prevention The research results that have been applied in production have initially brought about positive effectiveness in the development of orchid cultivation in Vietnam However, new researches have just been carried out on some objects and technical process for planting, taking adequate care of the orchids, especially Cattleya, Dendrobium and Oncidium, have not been completed

From the results of the study, it is shown that Cattleya, Dendrobium and Oncidium can fully grow and develop well in Vietnam, especially in the southern region due to the warm climate all the year round In the northern delta regions, due

to cold winter temperature, the plants can not grow and develop well, and very often there are virtually no flowering in winter time To develop and grow the orchid genus Cattleya, Dendrobium, Oncidium in condition of Northern Delta region, it is necessary to deeply study the growth, development and flowering characteristics of these cultivars At the same time, research on technical planting measures to increase survival rate, to reduce the incidence of soft rotten disease of seedlings in summer time and increase flowering rate, flower quality of mature plants in winter time for the introduced hybrid orchids belonging to the 3 above - mentioned orchid genera

Chapter 2 RESEARCH MATERIALS, CONTENT AND METHODOLOGY

2.1 Research Materials

2.1.1 Varieties:

- 5 Oncidium orchid cultivars, imported from Thailand, as seedlings after the stage of tissue culture, with height: 6-8 cm, number of leaves: 3-4 leaves/plant, number of roots: 5-7 roots/plant and one Oncidium cultivar which is widely planted

in production as the controls (cntrl)

5 Dendrobium orchid cultivars, imported from Thailand, as seedling, after the stage of tissue culture with height: 6-8 cm, number of leaves: 2-3 leaves / plant, number of roots: 4-6 roots/plant and one Dendrobium cultivar which is widely planted outside in production is used as the controls (cntrl)

- 6 one leaf Cattleya orchid cultivars imported from Thailand were used as seedling after the stage of tissue culture with height: 5-7 cm, number of leaves: 2-3 leaves/plant, number of roots: 3-5 roots/plant and 1 cattleyas which is widely planted in production outside was used as the control (cntrl)

2.1.2 Substrates:

The experiments included 5 types of substrates formula of differen mixing ratios

- Coal (charcoal), pine barks, light stones, volcano foaming slag, Seaweed

2.1.3 Leaf Foliars:

- Including 5 types of fertilizers: Growmore, Hidrophos, Multi K fertilizers, Striving buffalo, Milo-3 Distribution

2.1.4 Substances capable of regulating the growth(growth regulator):

- DD 1.8 Atonik, ProGibb 10 SP, Dekamon 22.43L

2.1.5 Substance capable of stimulating flowering:

- Asco Gold, RB, AT preparations

2.1.6 Other materials:

- Slow release root fertilizer N: P: K = 14:14:14, wires, Compax bulbs 75W and 100W, incandescent bulbs 75W and 100W, clamps ruler, tape-measure, electronic balance, light intensity meter, moisture meter

2.2 Research contents:

2.2.1 To evaluate the growth, development capacities and select some exotic hybrid orchid cultivars belonging to 3 orchid genera of Cattleya, Dendrobium, Oncidium adaptable to the North Delta area

2 2.2 Study some technical measures in the nursery stage for some selected exortic hybrid orchid cultivars belonging to 3 orchid genera of Cattleya, Dendrobium, Oncidium

2.2.3 Study some technical measures at the stage of production garden for some selected exortic hybrid orchid cultivars belonging to 3 orchid genera of Cattleya, Dendrobium, Oncidium

2.2.4 Study some measures to control flowering time for some selected exortic hybrid orchid cultivars belonging to 3 orchid genera of Cattleya, Dendrobium, Oncidium

2.3 Research Methodology and experimental design

* Methods of experimental design

- The experiments were designed in a randomized complete block design (RCBD) [33] with three replicates At nursery stage, each treatment consisted of

150 plants; at the garden production stage, each treatments consisted of 75 plants The observation, subscription and measurment on the growth and development criteria of the plants were conducted on30 plants/ treatment

2.3.1 Methods to evaluate the growth, development capacities and select some exotic hybrid orchid cultivars belonging to 3 orchid genera of Cattleya, Dendrobium, Oncidium

- Experiment 1: Study the growth at the nursery stage of the exotic hybrid orchid cultivars belonging to 3 orchid genera of Cattleya, Dendrobium, Oncidium

- Experiment 2: Study the growth, development and flowering capacity at the garden production stage of the exotic hybrid orchid cultivars belonging to 3 orchid genera of Cattleya, Dendrobium, Oncidium

2.3.2 Experiments on technical measures at the nursery stage

- Experiment 3: Effect of the seasonal planting time to the growth of the

seedlings at nursery stage

- Experiment 4: Effect of the type of substrates to the growth of seedlings at the nursery stage

- Experiment 5: Effect of some foliar fertilizer to the growth of the seedlings

- Experiment 7: Effects of shading system to the growth and development of selected orchid cultivar Den5

- Experiment 8: Effect of different types of substrates to the growth and development of selected orchid cultivar On1

- Experiment 9: Effect of some foliar fertilizers to the growth and development of selected orchid cultivar Cat6

2.3.4 Experimental study on some technical measures to control flowering time for the selected exotic hybrid orchid cultivars of 3 orchid genera of Cattleya, Dendrobium, Oncidium

- Experiment 10: To study the effect of types of additional lightings to flowering and flower quality of orchid cultivars Den5 and On1

- Experiment 11: To study the effect of additional lighting time to flowering

of orchid cultivars Den5 and On1

- Experiment 12: To study the effect of additional lighting time combining with plastic coverage to the ability of flowering to orchid cultivars Den5 and On1

- Experiment 13: To study the effect of flowering stimulants to flowering capacity of selected cultivar Cat6

2.4 The observation criteria

2.5 The conditions and equipment applied in experiments

2.6 Data processing

The study results are processed by biostatistics methods by computer software Excel and IRRISTAT software version 5.0

2.7 Locations and time of trials

- Experiments 1, 2, 3, 4, 5, 6, 7, 10, 11, 12 were carried out in the conditions

of Rhichel House at Van Giang Biological Experimental Camp, Agricultural Genetics Institute

- Experiments 8, 9, 13 were implemented in the conditions of seedling nursery nethouse in Phu Thuong Team - Management Board of Ba Dinh Square, Hanoi

- Trial time: 2006-2012

Chapter 3 RESULTS AND DISCUSSION

3.1 Assessment of growth and development and selection of some exotic hybrid orchid cultivars of 3 orchid genera Cattleya , Dendrobium, Oncidium

3.1.1 Some growth characteristics of exotic hybrid orchids at nursery stage

At the nursery stage , Oncidium and Dendrobium orchid have relatively high survival rate (48.7 to 72.2 %), the Cattleya orchid has lower survival rate (39.5 to 52.8 %) However, in the hot, humid summer conditions of the Northern Delta

region, soft rotten disease prevalence is relatively high, thus it has significantly reduced the proportion of seedlings ready for planting Therefore, in the nursery stage, applying technical measures (substrates, fertilizers, growth stimulants ) to reduce the incidence of soft rotten disease in seedlings is a critical necessity for

Plant hight (cm)

No of stems/

plant (stems)

No of leaves /plant (leaves)

Leaf length (cm)

Leaf width (cm)

Soft rotten disease severity (%)

Cat1 51.3 16.2 4.3 4.3 10.2 3.3 7.3 Cat2 43.3 13.7 3.6 3.6 8.6 3.0 18.5 Cat3 50.7 15.4 4.2 4.2 9.4 3.2 9.0 Cat4 39.5 14.1 3.0 3.0 8.1 3.0 36.3 Cat5 48.3 13.3 3.8 3.8 8.7 3.4 3.0 Cat6 52.8 16.5 4.4 4.4 10.6 3.5 8.7

Den1 61.5 21.1 3.4 10.5 12.4 2.2 4.7 Den2 48.7 22.3 2.1 9.3 10.7 2.3 16.5 Den3 52.1 20.5 2.7 9.2 11.5 2.6 2.3 Den4 63.7 22.8 2.6 8.1 12.2 2.4 7.0 Den5 65.6 22.6 3.9 10.4 13.6 2.4 8.0

On1 72.2 14.1 3.2 4.6 11.5 1.2 9.3 On2 68.6 16.8 3.7 4.8 14.1 1.5 22.5 On3 53.3 16.3 3.0 4.2 14.3 2.1 17.3 On4 59.1 17.5 3.3 4.7 13.7 1.9 8.7 On5 67.5 16.6 3.8 5.4 12.8 1.9 9.3

Seedlings at the nursery stage of the study, orchids grow well, have high

tillering ability to facilitate growth and development in the future This proves that

the imported seedlings at the nursery stage perfectly adapted to the ecological

conditions of the Northern Delta area

3.1.2 Some growth characteristics of exotic hybrid orchid at garden production stage

Table 3.2 Growth characteristics of exotic hybrid orchids at garden production stage (December, 2009 - Van Giang, Hung Yen)

Criteria

Cultivars

Plant height (cm)

Diameter (cm)

Number

of stems / plant (stems)

Number of leaves /plant (leaves)

Leaf length (cm)

Leaf width (cm)

The evaluation on the growth of exotic orchids at mature stage showed that

cultivars Cat6, On1 and Den5 have the best growth indicators