Grouping of Researched Pumpkin Varieties According to Yield Components

6740, 6916, 8382, 8396, 8576, 15113 and 19300; these are potential varieties.

quality energy, tastier and more nutritious for users and will be a valuable source of material for quality breeding.

6740, 6916, 8382, 8396, 8576, 15113 and 19300; these are potential varieties.

quality energy, tastier and more nutritious for users and will be a valuable source of material for quality breeding.

Table 3.4. Some quality indicators of studied pumpkin varieties

Nutritional composition

Note: Dry matter content (%) is classified according to TCVN 10696:2015 [20]; Classifications are based on the classification of the Nutrient Data Laboratory, United States Department of Agriculture (2006) [121].

Under the same growing conditions, the quality of the varieties is determined by the variety factor. Different varieties have different qualities. Pumpkin is a vegetable with high nutritional value, good for health, the higher the dry matter content in pumpkin, the greater the nutritional value in pumpkin. Dry matter content is the remaining content of pumpkin after the water has been removed during the drying process. The results of the dry matter content assessment of the research varieties are shown in Table

3.4 and Figure 3.11.

The evaluation results showed that the dry matter content of the studied pumpkin varieties had large differences, ranging from 2.2% to 19.0%. with an average value of 7.9%, a standard deviation of 2.6 and a coefficient of variation of 33.4%. The variety with the lowest dry matter content of 2.2% was Co Nhum (SDK-19326, collected in Bac Kan), with a yield of 13.6 tons/ha, a deep yellow flesh color, and a fruit weight of 1.7kg; The variety with the highest dry matter content of 19.0% was Nhum Xi (SDK-8387, collected in Son La), a high-yield variety, yielding 15.7 tons/ha, a deep orange flesh color, and a weight of 2.5kg.

Figure 3.11. Dry matter content of studied pumpkin varieties

Figure 3.10 shows that most of the seed samples have dry matter content in the range of 6-10%, accounting for 62.12% (82 seed samples), typically Pumpkin (SDK3634), Crow (SDK5355), Pumpkin (SDK7534); group

65

The group with low dry matter content < 6% includes 29 varieties (accounting for 38.28%) typically Pumpkin (SDK3726) (4.0%), Xeng to (SDK7546) (4.0%), Ma uc (SDK8385) (4.7%), Mac uc kho (SDK8393) (5.2%); the group with high dry matter content from 10% includes 21 varieties (accounting for 15.9%) of which 4 varieties have high dry matter content (>13%) including: pumpkin (SDK3630) (13.3%), pumpkin with long fruit (SDK6916) (13.5%), Nhum xi (SDK8387) (19%), Lang qua (SDK19291) (13.5%).

 -carotene is a precursor of vitamin A, when entering the body it will be converted into vitamin A to participate in the visual process , besides that it also participates in the metabolism of protein, lipid, glucid and mineral salts . When there is a lack of vitamin A, protein accumulation in the liver will decrease and albumin synthesis in the serum will stop. Lack of vitamin A also increases the phenomenon of kidney stones and reduces potassium in many other organs , one molecule of  -carotene will produce two molecules of vitamin A. Thus,

β- carotene is known to play a very important role in the body, studies

Recent studies have shown that β -carotene is also an agent against cancer cells and toxins caused by ultraviolet rays. For the repair of damage caused by ultraviolet rays,

 -carotene is even more effective than vitamin A (Gerardus & Grubben, 2004 [48]; Christophe Wiart, PharmD, PhD, 2012) [31].

The evaluation results showed that the studied varieties had an average β-carotene content (5-10 µg/g) of 81.1%. The varieties had a low β-carotene content (< 5 µg/g) of 23.5%. The remaining 13 varieties had a fair level (10 - 15 µg/g) of 9.8% and 2 varieties had a high content (>15

µg/g) accounting for 1.5% are the samples with registration numbers 15164 and 3722.

The vitamin C content of the studied pumpkin varieties ranged from 1.4 - 19.1 mg/100g; the majority of pumpkin varieties (57.6%) had a fairly high vitamin C content (5 - 10 mg/100g), while 40.1% of the varieties had a low level (<5 mg/100g).

The results of the assessment of Vitamin C content shown in Table 3.4 and Figure 3.15 show that: 53 samples (accounting for 40.1%) have a vitamin C content of <5 mg/100g; 67 similar samples (accounting for 50.8%) have a vitamin C content of 5 -

10 mg/100g; 10 varieties (accounting for 7.6%) reached 10 - 15 mg/100g and only 2 varieties (accounting for 1.5%) had very high vitamin C content (>15 mg/100g) which were two pumpkin varieties SDK 7955 (19.1 mg/100 g) and SDK 8396 (17.7 mg/100 g), equivalent to pumpkin varieties F1-LTP 868 [17] or imported Korean pumpkin varieties such as TN220 and Season opener [5].

3.1.4. Identify some promising pumpkin varieties for use as materials

Select and introduce production in the direction of high dry matter content and productivity.

The results of the study on the agrobiological characteristics of a group of 132 pumpkin varieties; analysis of genetic diversity of the gene source, grouping of varieties according to agronomic morphological traits, yield and analysis of the quality of the varieties are the basis for selecting starting materials in the research on breeding and exploiting and developing gene sources with high dry matter content and yield to serve the next research and introduce for production.

The results of the evaluation of the agronomic characteristics of the pumpkin group showed that the pumpkin varieties performed well in this trait but performed normally in another trait. Therefore, in order to select pumpkin varieties with high yield and suitable quality traits, the study used the selection program, version 1.0 of Nguyen Dinh Hien (1996), based on the following criteria: Actual yield, dry matter content, brix, β-carotene content and vitamin C content; with the following selection criteria: varieties with yield ≥ 15.00 tons/ha, dry matter content (%) ≥ 7.5, brix (%) ≥ 5.9, β-carotene content (µg/g) ≥ 8.6 and vitamin C content ≥ 2.50. Five criteria were included in the line selection program, of which 3 criteria (brix, β-carotene content and vitamin C) were not prioritized with a coefficient of 1; 2 priority criteria with a coefficient of 10 were actual yield and dry matter content. Based on the combined criteria, the closest varieties were selected compared to the set target based on the Euclidean distance (this distance did not take into account the relationship between the criteria). The results showed that 14/132 pumpkin varieties met the above selection criteria, presented in Table 3.5 and Appendix 7.

Table 3.5. Selection results of 14 promising pumpkin varieties according to the line selection program (Selection Index)

TT

In which the registration number (SĐK) at the Gene Bank, variety name and collection location are as follows:

TT