Growing media is defined as the mean where the roots of cultivated plants grow (Kampf 2000) and the primordial function gives support to growing of plant (Kampf 2000, Robert 2000). Growing media should be considered as an essential part of the propagation system because rooting competency depends on the type of medium used (Chadha 2007, Mehmood et al 2013). Rooting medium directly effects quality and percentage of rooting (Loach 1988). The growing media should be porous, uniform in texture, hold sufficient moisture and should be well drained (Sardoei et al 2014) which provides physical support, aeration and water (Hartmann et al 2011, Larsen and Guse 1997, Bhardwaj 2014). According to Loach (1988) the rooting medium should be considered as an integral part of the propagation system; percentage rooting and the quality of the roots produced are directly influenced by the medium. The type of rooting media and their characteristics are of greatest importance for the quality of rooted cuttings (Khayyat et al 2007). The selection of the proper media components is critical to the successful production of seedlings (Robins and Evans 2011) because media play an important role in seed germination and directly affect the development and later maintenance of the extensive functional rooting system (Bhardwaj 2014).

The genus Terminalia is the second largest genus of the Combretaceae family with about 200 species. These plants are distributed in tropical regions of the world with the greatest genetic diversity in southeast Asia (Lima et al 2012). Terminalia tomentosa Roxb is a large deciduous tree, 20-35 m high and 1 m in diameter (Nadkarni 1976, Nair and Henry 1983, Rastogi and Mehrotra 1991, Shetty and Singh 1987). It is commonly known as Ain, Asan, Indian Laurel and silver grey wood and is casually called crocodile bark tree due to its characteristic bark pattern. It is a primary host plant for the larvae of tropical tasar silkworm reared for commercial production of cocoon.

The bark is bitter and stypic, useful in vitiated conditions of pitta, ulcers, vata, fractures, haemorrhages, bronchitis cardiopathy, strangury, wounds, haemoptysis, dysentery, cough, verminosis, leucorrhoea, gonorrhoea and burning sensation (Kirtikar and Basu 1935, Warrier et al 1993). Phytoconstituents such as tannins like arjunic acid, arjunolic acid, arjunetin, ellagic acid, gallic acid and triterpenoids like oleanolic acid, betulinic acid and steroid like β-sitosterol have been reported to be present in T tomentosa (Row and Rao 1962, Mallavarapu et al 1980, Mallavarapu et al 1986, Anjaneyulu et al 1986, Srivastava et al 2001). The plant is known to possess many pharmacological properties like antifungal (Shinde et al 2011), antioxidant (Jain et al 2010), anti-hyperglycaemic (Alladi et al 2012), anti-diarrhoeal and anti-leucorrheal (Hedge et al 2009). The multipurpose tree species T tomentosa is grown generally on field bunds in Konkan region of Maharashtra. Apart from its economic value the tree is important silviculturally as being one of the commonest of Indian forest trees and being suitable for afforesting clayey ground.

It is absolutely determined that use of appropriate growing medium helps in the production of quality planting material with better root system and enhances final survival of tree species. This further helps in lowering the cost of planting material that successfully is going to be helpful for the farmers. Therefore keeping in view the above facts, the present study was undertaken.

Seeds were collected form superior trees of T tomentosa (10-15 years old) from biodiversity park of College of Forestry, DBSKKV, Dapoli, Maharashtra (latitude 17°452 N, longitude 73°122 E, altitude 250 m amsl) in the month of March 2021. Dapoli is located in the Konkan region of Maharashtra and is confined in between Sahyadri hills in the east and Arabian Sea in the west. Dapoli represents more or less tropical climate having average humidity of 78 per cent throughout the year. The climate is hot, humid with well-expressed three seasons viz summer (March to May), rainy (June to October) and winter (November to February). The average minimum and maximum temperature is 18.5 and 30.8°C respectively with an average annual precipitation of 3,500-4,000 mm which is generally received from June to October.

The experimental treatments comprised seven treatment combinations consisting of different combinations of growth media. There were seven treatments viz T₁ [Control (soil)], T₂ [Control (cocopeat)], T₃ [Control (vermicompost)], T₄ [Soil:vermicompost:cocopeat (2:1:1)], T₅ [Soil:vermicompost:cocopeat (1:1:1)], T₆ [Soil:vermicompost:cocopeat (1:2:2)] and T₇ [Soil:vermicompost:cocopeat (1:1:2)] with three replications. The experiment was laid out in complete randomized design. There were 10 polythene bags in each replication having the size of 12.5 cm x 25 cm. Polythene bags were kept moist by sprinkling water and kept free from weeds. To protect the polythene bags from fungal diseases, drenching of carbendazim (@ 2 g/l was done in alternate weeks. The seed germination was monitored daily. The seed germination was calculated using the following formula

At the end of the experiment, five seedlings per replication were randomly selected and carefully uprooted without breaking the roots for seedling growth studies.

Shoot length was measured from leading shoot tip to the collar region of the seedling. Root length of tap root was recorded by placing it horizontally on the ground. Collar diameter of the seedling was measured by the vernier caliper. Fresh root and shoot weight was calculated with electronic balance. Root-shoot ratio was calculated by dividing root length by the shoot length of the seedling. Vigour index and sturdiness were worked out using the following formulae:

ANOVA was applied by using the statistical package SYSTAT (9.0). When the treatment effect was found significant, the least significant difference (LSD) was calculated to compare treatment means. The graphs were prepared by using MS Excel.

The data given in Table 1 show that germination was maximum in treatments T₅ [Soil:vermicompost:cocopeat (1:1:1)] (76.67%) and T₆ [Soil:vermicompost:cocopeat (1:2:2)] (70.00%) which were at par followed by T₇ [Soil:vermicompost:cocopeat (1:1:2)] (60.00%) as compared to T₁ [Control (soil)] (36.67%). Collar diameter was recorded maximum in T₅ (2.92 mm) followed by T₆ (2.61 mm) and minimum in T₁. Shoot length was also maximum in T₅ (12.40 cm) followed by 10.40 cm in T₆ and minimum in T₁ (5.90 cm). Root length was recorded maximum in T₅ and T₆ (12.60 and 11.70 cm respectively) both being at par as against minimum in T₁ (7.73 cm). However root-shoot ratio was highest in T₁ (1.33) followed by 1.13 in case of T₆. Vigour index was also recorded maximum in T₅ (1,915.67) followed by 1,541.63 in T₆ and minimum in T₁ (502.00). Fresh shoot weight was recorded maximum in T₅ (1.42 g) and T₆ (1.36 g) the two being at par followed by 1.20 g in T₇ and minimum in T₁ (0.67 g).

In case of fresh root weight T₅ (0.54 g) recorded maximum fresh root weight followed T₆ (0.47 g) as against the minimum in T₁ (0.35 g). Maximum sturdiness was recorded in T₂ [Control (cocopeat)] (5.62) and T₄ [Soil:vermicompost: cocopeat (2:1:1)] (5.14) followed by 5.02 in T₂ [Control (cocopeat)]. From the observations it is apparent that among the seven treatments, T₅ was found significantly superior treatment as compared to others.

The type of rooting media and their characteristics are of utmost importance for the quality of rooted cuttings (Khayyat et al 2007). The effects of different pot mixtures on plant growth and development have been previously investigated (Douglas et al 2000, Nowak and Strojny 2003, Samartzidis et al 2005). Singh and Mann (1976) planted the seedlings of trifoliate orange (Poncirus trifoliate) in seven different planting media and after eight and twelve months they found maximum number of leaves 29.5 and 48.8 respectively in soil treatment. Parasana et al (2013) found that soil + sand + farmyard manure mixture (2:1:1) was most effective for better germination (77.33%) of mango stones as well as growth of mango seedlings.

Vermicompost provides adequate nutrients and enhances both physical properties and water holding capacity of the soil. Combined application of vermicompost and cocopeat has shown significant effect on seedling growth and plant biomass, perhaps due to the synergistic effect of these two. The findings are as per the observations made by Abirami et al (2010) who reported that since coir dust is low in nutrients, mixed with vermicompost it provides a better growth medium for plant establishment. However cocopeat has been recognized as having relatively low levels of mineral nitrogen (N) and micronutrients such as calcium (Ca₂⁺) and magnesium (Mg₂⁺) (Evans et al 1996, Abad et al 2002).

References