Hey mukesh !
Partisan nd defection law.... which is also know as the Anti-Defection Law....was passed in 1985.
the main moto of this law was to stop the cruption in political parties.....
According to this Act, a member of the House belonging to one political party would be disqualified from his membership if he joins another political party.. after the election !!

आसान शब्दो मे कहा जाए तो.... घूँसखोर नेंताओ की फाडने के लीए ये law pass कराया गया था ।।

कुछ चुतीए नेता चुनाव के बाद opposition party से पैसे लेकर उनके तरफ हो जाते थे, जिसके कारण opposition party की सरकार बन जाती थी ।।

पर ये law paas होने के बाद, अगर कोइ नेता party बदलता है तो उससे अपनी position गवानी परेगी ।।

hope u got it man !!